Elements

Key Questions

• What is a chemical element?

  A chemical element is a pure substance that consists of atoms with the same number of protons in the nucleus.

  For example, carbon, nitrogen, and oxygen are elements. Their atoms have six, seven, and eight protons, respectively, in their nuclei.

  Other examples of elements are iron, copper, gold, mercury, and lead.

  Ernest Z. · 1 · Apr 14 2014

• What periodic table elements are radioactive?
• How can the periodic table be used to predict the properties of the elements?
• How can elements have different isotopes?
• How can elements be broken down?
• How can elements properties be predicted?
• What is a chemical element?
• What element in the fourth period of the periodic table has 5 valence electrons?
• How are chemical elements diffrent from chemical compounds?
• What does organic chemistry study?
• How do elements change from left to right in the periodic tabale?
• What chemical elements are considered primary elements?
• Which family of elements contains metals, nonmetals and metalloids?
• Why do different elements make different color flames when you burn them?
• Question #3540d
• Question #1847d
• Question #18965
• Question #aec3a
• Question #7e1c8
• Question #195a0
• Question #1514c
• Question #77df1
• Question #f5b25
• Question #3db59
• Question #6e2b4
• Question #09fa1
• Which is molecular: xenon; argon; barium; iodine; potassium?
• Question #7cf45
• Question #a4223
• Question #dd483
• Is silicon (Si) a metal, metalloid, or non-metal? Explain.
• Elements are pure substances made up of only one kind of what?
• What is the difference between a coefficient and a subscript?
• Question #418af
• What is the origin of the term 'elements'?
• What is the chemical symbol for the element neptunium?
• How is mercury different from other metallic elements?
• What is nickel most used for in the U.S.?
• Question #87e4a
• Question #02449
• Is mercury a heavier element than tin?
• Question #36a13
• Can you account for the Periodic Table given electronic structure?
• Why are most materials compounds rather than elements?
• What element has 47 protons in its nucleus?
• What elements would have similar properties to Sulfur?
• Question #0aef7
• Question #a4bfb
• Which tells us more about an element's properties, its row or its column? Why is this?
• What is the correct symbol for the atom with 42 protons and 49 neutrons?
• How is the element Magnesium made or acquired?
• Question #7221f
• How many different elements are found in #H_2SO_4 + 2KOH -> K_2SO_4 + 2H_2O#?
• Question #53543
• Question #10bdd
• About how many elements form all substances?
• What are some positive ways arsenic is used?
• If we have an atom for which #Z=17# that possesses #"16 electrons"#, how would we represent it symbolically?
• What are properties of silver that make it easy to work with?
• Copper has a specific gravity of 8.9: what does this mean?
• What are two ways that elements can be made?
• Compare the reactivities of sulfur and calcium?
• What are the elements in the second third, fourth, and fifth periods that have the same number of highest-energy-level electrons as bariu.?
• Is fluorine more reactive or less reactive than chlorine?
• What are three forms of the element carbon?
• Question #3d849
• What is the element whose sulfide is known as #"stibnite"#?
• Question #fe61d
• Diamonds and graphite are two forms of what nonmetal?
• What is a flame test used for?
• Question #0fe12
• Why are neither the alkali metals nor the alkaline-earth metals found uncombined in nature?
• What are the six most abundant elements in seawater?
• In what two ways can elements occur in nature?
• Which region of the electromagnetic spectrum is involved in mass spectroscopy ? a. visible. b. radiowave c. microwave d. none of these
• Question #875ac
• Who discovered phosphorus?
• Why is diamond classified as an allotrope of carbon?
• Which element on the periodic table has a total of 16 protons?
• What properties of carbon explain carbon's ability to form many different macromolecules?
• What are f block elements?
• How can you learn f block elements?
• How many f block elements are there?
• What are f block elements known as?
• What are the f block elements in period 7 known as?
• What are the f-block elements in period 6 known as?
• Why are f block elements placed separately?
• Why are transition metals called D-block elements?
• Why is scandium outer electron configuration #4s^2 3d^1# and not just #3d^3#?
• How do you figure out the charge of an element that is located in the d-block of the periodic table?
• Why are d and f block elements called transition elements?
• What groups of elements does the d-block contain?
• Why is Fluorine more reactive than Argon?
• Which element has 47 electrons?
• What family of elements are the most reactive metals?
• Question #ea213
• How are nickel, calcium, magnesium, and antimony classified?
• In which block of the periodic table is chromium found?
• What is a transition metal?
• What are transitional elements in chemistry?
• What are the representative elements, transition elements and inner transition elements?
• How would you classify the following elements as main group elements, transition metals, or inner transition metals: 1.Ca 2.Fe 3.Ag 4.U 5.O 6.Pb?
• Which one of the following elements is a transition element? Why?
• What subshell is partially filled in the transition metals?
• Transition elements, such as chromium, are likely to have what type of oxidation number?
• Which of the following elements are transition metals: Cu, Sr, Cd, Au, Al, Ge, Co? How can this be determined?
• Why do transition elements exhibit such a variety of coloured compounds, complexes and different oxidation states?
• What are transition elements?
• What type of ions are formed by transition elements?
• What is the charge (positive or negative) of transition metals?
• How are transition elements used?
• How do transition elements form coloured compounds?
• How do transition elements form coordination compounds?
• How do transition elements form ions?
• How many inner transition elements are there?
• How many transition elements are there?
• What category of elements does krypton gas belong to?
• Which element was first discovered in space before it was discovered on Earth?
• How do you find metalloids on the periodic table?
• What are the six metalloids on the periodic table?
• What are three metalloids on the periodic table?
• What are two metalloids on the periodic table?
• Why are metalloids located on the periodic table?
• How can a flame test identify an unknown element?
• Question #16971
• Why is it that d-block metals occupy the #d# orbitals a lot of the time, whereas f-block metals occupy the #d# orbitals much less often? Can electronic transitions occur within the valence space of f-block elements?
• What is the abbreviation of Lanthanide?
• Question #05cb7
• What shows an element's number of protons in its nucleus?
• Which mineral is necessary for proper synthesis and function of the hormone thyroxine?
• What do the elements lithium, sodium, and potassium have in common?
• Are more than three-fourths of the elements in the periodic table nonmetals?
• How can the number of atoms of an individual element be determined by usung a chemical formula?
• What is the smallest particle of an element that retains the properties of that element?
• Question #1eae8
• What is the dominant form of breakage for sulfur?
• How many core electrons are in a ground state atom of arsenic?
• How does a lithium cation compare to a lithium atom?
• A chemical element is a pure substance that consists of only one type of what?
• What is a pure substance that consists entirely of one type of atom?
• An element has three naturally occurring isotopes with the following masses and abundances. How do you calculate the atomic mass of this element? What is the identity of the element?
• Does Hydrogen fuel require vast amounts of electricity?
• How many protons, neutrons, and electrons does a neutral hydrogen atom have?
• Why is phosphorus necessary for life?
• What is carbon used to form?
• What element can be represented by 45 #n^o#, 34 #p^+#, 34 #e^.#?
• How many protons, neutrons, electrons, energy levels and valence electrons does Boron (B) have?
• Sulfur is a common starting material for the Contact process. What is a source of sulfur?
• If an element has 14 electrons how many protons are present in the atom?
• What is made of two or different elements chemically combined ?
• Because of the arrangement of carbon's electrons it tends to form long what?
• Question #de296
• What is the oxidation state of a free element? Of a monoatomic ion?
• A new penny has a mass of 2.49 g and a volume of 0.349 #cm^3#. Is the penny made of pure copper? Wy or why not?
• What is the element with symbol As?
• What element has the symbol Kr?
• What is the element with symbol Al?
• What element has the symbol Ni?
• What is the element with symbol Ar?
• What is the element with symbol Ge?
• What is the element with symbol Bi?
• What is the element with symbol Xe?
• What is the element with symbol N?
• What element has the symbol Ag?
• What element has the symbol Rn?
• What is the element with symbol Na?
• What is the element with symbol Au?
• What are elements, compounds, and mixtures?
• From the first 20 elements, can you name an element made up of diatomic molecules with a single bond between the atoms?
• Why is the smallest unit that retains the properties of an element?
• What are the most abundant elements in the body?
• Approximately how many elements occur naturally on earth?
• What is associated with hydrogen?
• Why does oxygen (O) not have a subscript/number?
• What elements make up water?
• What are all alike in the same element?
• What element is used in thermometers?
• Sodium chloride is a compound of sodium and chlorine, which of these elements is the alkali metal and which halogen?
• There are 92 of what type of elements?
• What element is used in some balloons?
• What is an element used to make soft-drink cans?
• What do the four elements most abundant in life- carbon, oxygen, hydrogen, and nitrogen- have in common?
• What properties of carbon explain carbon's ability to form different large and complex structures?
• What the symbol for an element that is a halogen?
• What the symbol for an element that is an alkali metal?
• What the symbol for an element that is a noble gas?
• What the symbol for an element that is an alkaline earth metal?
• Why are Carbon atoms the most versatile molecular building blocks used by living organisms?
• Certain elements have special affinities for other elements. This causes them to bind together in special ways to form what?
• What should you do with a worn-out Li-on battery?
• What is the physical state of neon at room temperature?
• What is the physical state of oxygen at room temperature?
• What is the physical state of mercury at room temperature?
• Which element is most chemically similar to the element indicated by the letter E in the following periodic table?
• Which four elements are the primary components of important biological molecules, such as proteins, fats and carbohydrates?
• No other element can form the amount and variety of molecules that carbon can form. What characteristics does carbon have that explain this characteristic?
• What type of atom is sodium?
• What type of atom is neon?
• What type of atom is oxygen?
• What type of atom is phosphate?
• What type of atom is magnesium?
• What type of atom is nickel?
• What three elements are needed to start a fire?
• What element is found in amino acid that isnt found in simple sugors like glucose or fructose?
• How many more protons does sodium have than oxygen?
• If we are converting phosphorus from 3.44 moles to atoms, why do we sometimes do mole -> atoms? Instead of doing moles -> molecules -> atoms?
• What is the smallest particle of an element that can exist called?
• What is Sodium's number of protons?
• What is Flourines number of protons?
• What element has symbol of F?
• What element has symbol of N?
• What element has symbol of O?
• What element has symbol of Am?
• What element has symbol of Ar?
• What element has symbol of Na?
• What element has symbol of Cl?
• What element has symbol of Zn?
• What element has symbol of Cd?
• What element has symbol of K?
• What element has symbol of Li?
• What element has symbol of Rg?
• What element has symbol of Al?
• What element has symbol of C?
• What element has symbol of B?
• How did Lavoisier help to transform chemistry?
• Question #058cb
• Where did the noble gases get their name?
• What do protons determine about an element?
• How can pure oxygen be obtained from air?
• What are elements?
• What are the elements?
• What are elements composed of?
• How many elements are on Earth?
• How are elements formed?
• What is one property of copper?
• What is one property of nitrogen?
• What is one property of oxygen?
• What is one property of phosphorous?
• What is one property of silver?
• What is one property of chlorine?
• What is one property of sodium?
• What determines how reactive an element is?
• What is one property of neon?
• What is one property of helium?
• What is one property of aluminum?
• What is one property of tungsten?
• What types of elements make up nucleic acids?
• There are about 115 elements, each of which has its own chemical what?
• Phytoplankton are said to release how much of the oxygen in Earth's atmosphere?
• What is the full name of this element?
• What are the main sources of nitrogen oxides in the atmosphere?
• How do you name and classify Kr and Xe?
• An unknown element is shiny and is found to be a good conductor of electricity. What other properties would you predict for it?
• Question #142a1
• What is a third period dianion?
• Living organisms are composed of millions of organic compounds, each having a unique structure. What element is responsible for this huge diversity of molecules?
• Are oxygen atoms different from the atoms of other elements?
• What are 5 elements named after countries?
• What are 5 elements named after people?
• What is the number of neutrons in #""_(5)^(10) "B"#?
• What do halogens include?
• What is one element in the which is a gas at room temperature and in which the atoms are joined together in molecules?
• What are the Group 3 elements called?
• What are the Group 6 elements called?
• What does Element mean?
• An atom of calcium has 20 protons, how many electrons does it have?
• What elements are least abundant in the universe?
• What do all atoms of all elements have in common?
• Question #a895e
• What is the symbol of the element in Group 4 and Period 2?
• What is the symbol of the element in Group 4A(14) and Period 2?
• Which two gases make up 99 percent of the gases in the atmosphere Which gas is more abundant?
• Can atoms of the same element differ in the number?
• What one element from an distinguishes other?
• What are the simplest pure substances that cannot be broken down chemically into other substances?
• How do you find the number of electrons in an element?
• Evaluate the physical properties of potassium, magnesium, and copper. Select the best choice to use for a building project. Why is this metal the best building material to use?
• What are all the halogens?
• What are two elements that would have properties similar to beryllium?
• What are two elements that would have properties similar to silver?
• What are two elements that would have properties similar to gold?
• What are two elements that would have properties similar to nickel?
• What are two elements that would have properties similar to iron?
• What are two elements that would have properties similar to argon?
• What are two elements that would have properties similar to xenon?
• What are two elements that would have properties similar to tungsten?
• What are two elements that would have properties similar to copper?
• What are two elements that would have properties similar to sodium?
• What are two elements that would have properties similar to oxygen?
• What are two elements that would have properties similar to neon?
• What are two elements that would have properties similar to sulfer?
• Is Magnesium a solid, liquid, or gas at room temperature?
• Is neon a solid, liquid, or gas at room temperature?
• Is titanium a solid, liquid, or gas at room temperature?
• Is platinum a solid, liquid, or gas at room temperature?
• Is oxygen a solid, liquid, or gas at room temperature?
• What are two elements that would have properties similar to magnesium?
• Is xenon a solid, liquid, or gas at room temperature?
• Is radon a solid, liquid, or gas at room temperature?
• Is hydrogen a solid, liquid, or gas at room temperature?
• Is potassium a solid, liquid, or gas at room temperature?
• Is sodium a solid, liquid, or gas at room temperature?
• Is chlorine a solid, liquid, or gas at room temperature?
• What are two elements that would have properties similar to chlorine?
• Is gold a solid, liquid, or gas at room temperature?
• Is silver a solid, liquid, or gas at room temperature?
• Is boron a solid, liquid, or gas at room temperature?
• Is beryllium a solid, liquid, or gas at room temperature?
• Is nitrogen a solid, liquid, or gas at room temperature?
• Is argon a solid, liquid, or gas at room temperature?
• What is the relationship among atoms, elements and compounds?
• What do these four elements - carbon, hydrogen, oxygen, and nitrogen, make up more than 96% of?
• What is the formation of ammonia from its its elements?
• What are the allotropes of carbon ?
• Why do lithium, sodium and potassium float on water?
• How many electrons do beryllium have?
• How many electrons does hydrogen have?
• How many electrons does helium have?
• How many electrons does copper have?
• How many electrons does gold have?
• How many electrons does silver have?
• How many electrons does neon have?
• How many electrons does calcium have?
• How many electrons does magnesium have?
• How many electrons does manganese have?
• How many electrons does boron have?
• Question #9e2ae
• Question #782fd
• What is Radon? Should you worry about it?
• Which of these elements is found in the smallest amount in living matter?
• I am a member of the boron family and am the most abundant metal in the Earth's crust. What am I?
• I am the head of the carbon family known as the "basis of life#? What am I?
• What is #Z_"atomic number"# for hydrogen?
• What element has the smallest atomic radius?
• What element has the largest atomic radius?
• Is nitrogen reactive?
• Is oxygen reactive?
• Is copper reactive?
• Is xenon reactive?
• Is helium reactive?
• Is calcium reactive?
• Is iron reactive?
• Is magnesium reactive?
• Is fluorine reactive?
• Is argon reactive?
• Is sodium reactive?
• What element is dull, not malleable, and a poor conductor of electricity?
• Question #f41d2
• Is neon stable?
• What is a process for removing impurities from crude iron?
• What are the component elements of sodium chloride?
• How many oxygen atoms are present in a formula unit of potassium sulfate?
• Why do some elements have symbols that are very different from the English names of the elements?
• What is the element that makes up 78% of the atmosphere?
• What happens when a pellet of sodium is sliced in two?
• What does the color of each elements symbol represent?
• Why are the spheres representing nitrogen and oxygen different colors?
• In what state are you most likely to find sodium?
• Why is chlorine more reactive than iodine?
• What supports the column of mercury inside the glass tube of a barometer?
• What characteristics are shared by calcium and magnesium?
• What is a pure substance that cannot be broken down by chemical or physical means?
• What elements are present in #Na_2(OH)_4#?
• What are the names of all the elements in #Na_2(OH)_4#?
• How do we determine the reactivity of the halogen elements?
• The salts of which ion, #M^+# or #M^(2+)#, are more likely to form an hydrate? Does hydration refer to the number of water molecules?
• What is an element that often combines with metals to form important ore minerals near hydrothermal vents?
• What is #"nascent oxygen"#?
• Do elements have similar chemical and physical properties when they are located in the same group or period?
• What do #He#, #Ne#, and #Ar# have in common?
• What are many elements a mixture of?
• What is the difference between the formula #CO# and the symbol #Co#?
• What is a substance that cannot be broken down into simpler substances?
• What are the three major gases present in the atmosphere?
• What do many elements found in nature exist as?
• What is the most abundant element in the universe?
• What does the number 232 represent in Thorium?
• What must two atoms have the same if they represent the same element?
• What is the most common gas in the air?
• What two actinides occur naturally on on Earth?
• What special name is given to the group of elements that are monatomic at room temperature?
• What would happen if oxygen were not available?
• What gases in Earth's atmosphere would you expect to find as molecules and which as individual atoms?
• What is the abbreviation for calcium?
• How is helium different from neon and argon? How is it similar?
• Why does the air have nitrogen?
• Which element has 2 valence electrons and is in period 4?
• How many bonds can Carbon form? Why is this important?
• What does the nucleus of an atom of cobalt-58 contains?
• Of the following series of elements....which one is MOST REACTIVE, and which one is LEAST REACTIVE?
• What are all elements made of?
• Is fluorine molecular?
• Why do you think neon is used in signs?
• Which noble gas makes up about 1 percent of Earth's atmosphere?
• Where are the halogens located in the periodic table?
• Question #4a82b
• Question #d9f6a
• What can you infer about copper and silver based on their position relative to each other?
• How are potassium atoms formed from potassium ions?
• Why does helium exist only as single atoms?
• Which gas did Jacques Charles discover could be used as the source of hot air for a hot air balloon's envelope?
• How many electrons does #K^(1+)# have?
• Is chlorine a metal or a nonmetal?
• Is sodium a metal or a nonmetal?
• How can Xenon and Krypton form compounds with Fluorine if they are inert gases?
• How do you determine if an element is a transition element?
• Why is neon inert?
• What is a common use for chlorine?
• What are two atoms of the same element with different mass numbers called?
• At STP a 7.49-gram sample of an element has a volume of 1.65 cubic centimeters. What is the element?
• #O_2# and #H_2# are the same gas at what temperature?
• What is lithiums state of matter?
• An atom has 9 protons and 10 neutrons. What is the atomic number, the mass number and the symbol for this element?
• How did the element Uranium get its name?
• What elements are liquid at room temperature?
• What are all the elements the oxygen family?
• What are the four essential elements for life?
• What is the most common type of element?
• A neutral atom of sodium has 11 protons. How do you use this information to explain the total number of electrons that are in a sodium atom?
• Why would prefer to use the mercury instead the water in a sphygmomanometer?
• When does an element become a positive ion?
• What halogens are gases at room temperatur and pressure?
• If element A floats when placed in element B what can you deduce about the elements?
• What is the number of electrons in a potassium atom?
• What is the number of electrons in a carbon atom?
• What charge does a proton have?
• How many protons and how many electrons are in an oxygen ion that has a -2 charge?
• Iodine is an element in Group 7A of the periodic table. Which type of ion does iodine form?
• To which group do the alkaline earth metals belong?
• How do you determine the number of neutrons in carbon?
• The nitrogen-14 isotope has a mass number of 14 and an atomic number of 7. How many neutrons does it have?
• An iron atom has an atomic number of 26 and an atomic mass of 55.8 amu. How many protons does an iron atom have?
• What are the similarities and differences you would expect in the properties of silicon and diamond?
• How does helium differ from the other noble gases?
• Does neon combine easily with other elements? Why or why not?
• What is the most chemically active element?
• What is the most stable potassium ion?
• What is the most stable iodine ion?
• Gold has the highest what for the ability to be pulled into then water?
• What ion of barium is most stable?
• How many ionic protons are in calcium?
• #Na^+# is the chemical symbol for what ion?
• What is an atom that has gained or lost electrons called?
• Which elements in the actinide series are transuranium elements?
• What is one practical use of the element americium?
• Why does a hot air balloon rise when it ls heated?
• Question #f221a
• What is unique about carbon?
• Why don't equal masses of carbon atoms and oxygen molecules contain the same number of particles?
• Atoms of which element have two protons and two electrons?
• Which Group 16 element combines with hydrogen to form compound that has the strongest hydrogen bonding between its molecules?
• Atoms of which elements tend to gain electrons? Atoms of which elements tend to lose electrons?
• All living organisms contain carbon atoms. What are the important characteristics of carbon to enable this?
• Post 1984 pennies are composed of a zinc core and a copper shell. Why is this best?
• What are the characteristics/properties of the noble gases?
• An atom that has 117 protons in its nucleus has not yet been made. Once this atom is made, to which period and group will element 117 belong?
• Approximately how many elements are in the universe?
• What makes an element unique?
• Except for helium, how many electrons do noble gases have in their outer energy levels?
• Why are incandescent lamps with tungsten filaments filled with an inert gas such as argon?
• How did the element iron get its name?
• What are two major elements common in Europe and what is made with them?
• What type of element is nitrogen?
• Atoms of which element have the greatest tendency to gain electrons?
• How does the composition of most minerals differ from a pure element?
• How is each element unique on the periodic table?
• A substance consists of atoms which all have the same number of protons and electrons but different numbers of neutrons. Why is this substance an element?
• How are the negative fluoride ions formed from fluorine atoms?
• What is the total charge of the nucleus of a carbon atom?
• Which element has the largest atomic radius?
• What did scientists divide elements into?
• What is the letter "C" for the element carbon?
• How would you write the following elements as an ion: S, Mg, Br, Al?
• Potassium ions (K^+#) have a positive charge. What happens to a potassium atom's electrons when it becomes an ion?
• What element has the highest melting point of any metal?
• What are different forms of the same elements with different number of neutrons?
• Why might chlorine be added to drinking water?
• Sodium is more reactive than lithium. Why?
• What gas has 8 protons and 8 neutrons?
• Question #a419b
• What are the allotropes of carbon?
• Question #56530
• What is a halogen element?
• Question #156b5
• A neutral atom containing ten negative charges is what element?
• What are the gases in Earth's atmosphere in order of most abundant to least?
• Question #3f232
• Question #c54f5
• Question #e45b9
• What would the symbol be for a particle that has 11 protons, 12 neutrons, and 10 electrons?
• Approximately how many elements are known today?
• Which properties would NOT be associated with the alkali metals? #"A. High densities."# #"B. Low atomic masses."# #"C. Lustre."# #"D. Reactivity with water."#
• The properties listed in which option is NOT necessarily consistent with those of an alkaline earth metal? #"A. Forms a salt with TWO equivs of halide."# #"B. Forms a simple binary oxide."# #"C. React with water to give dihydrogen."# #"D.Are ductile"#
• How can carbon and hydrogen atoms both be composed of the same elements but be different compounds?
• What is the element symbol for californium?
• What would be different in your observations between Na and K?
• What is the name for the group of elements that are particularly unreactive?
• Question #ca166
• What is an example of a halogen?
• Does oxygen exists in the air as comidiat molecules?
• Is about 20 percent of the air made up of the element geonyx?
• What are diamond and graphite in relation to carbon?
• What are diamond and graphite?
• Is aluminum a building material?
• Is aluminum a semiconductor?
• Is carbon a building material?
• Is carbon an allotrope?
• Is selenium an allotrope?
• Is selenium a building material?
• How many types of atoms are in carbon?
• What are the number of types of atom in the element carbon?
• Is phosphourus an allotrope?
• How can you determine if an element is toxic?
• What group number is carbon in?
• What is the colour of freshly sublimed iodine?
• What is an example of two elements with similar properties and an explanation of how you know?
• What is the secondmost abundant element in the universe?
• What is the valency of the element?
• What are the most abundant elements in the universe?
• Question #196a7
• Nitrogen is a key element in the formation of what, which are substances necessary to living organism?
• Question #1bcba
• A chemical symbol represents what of an element?
• Group 18 rarely combines with other elements. They are the "loners" or noble gases. Why do these elements not need to bond with other elements?
• How does the electronic structure of the Noble Gases account for their lack of reactivity?
• Question #57574
• Why are #"H^+# ion and proton synonymous?
• Why are plastics good insulators?
• What are the elements in coal?
• What element is always a part of combustion?
• How does cyanide work?
• Noble gases are monatomic. What does monatomic mean?
• What is the major gas in the atmosphere?
• Question #57e12
• What are substances that are at their simplest state called?
• Are all elements in group 17 metals?
• Question #00b7b
• Can all solids sublime?
• Where on the periodic table are metals found?
• Question #d26e1
• How does the nucleus of a copper atom compare to the nucleus of a nickel atom?
• What precautions would you take before testing the behavior of rubidium (Rb) in water?
• What are three halogens and describe a property that they all share?
• Question #99268
• What properties enable carbon to form polymers and so many other compounds?
• Tin added to what makes bronze?
• Why do the negative ions have larger radii than the positive ions?
• What is the abbreviation for sodium?
• What is a combining form for potassium?
• Where does most of the sulfur in coal originate from?
• Why can a hydrogen atom become either an ion or a part of a molecule?
• Question #817c0
• Question #a0290
• Question #1835b
• Why is colored alcohol used as the liquid in a weather thermometer rather than mercury?
• How many protons does an aluminum atom contain?
• What element has the most similar properties to sodium?
• What is the last sublevel filled for carbon?
• What are examples of chemical formulas representing a diatomic molecule?
• Which element is in the p block, has 6 valence electrons and is in period 3?
• What is the combining form meaning calcium?
• Is #H_2# classified as an element?
• Why is graphite soft, and why is its melting point so high?
• What is the total number of electrons in an atom of Cu-65?
• Why does calcium have a higher melting point than potassium?
• Question #572c6
• How does a neon tube work?
• What is a positive or negative number assigned to to an element?
• #NH_4C_2H_3O_2#, is made of how many elements?
• What is the only metal that is liquid at room temperature?
• What are the group 18 elements called?
• What is the basic unit of any element?
• Why is mercury ideal for use in thermometers?
• Neutral flame is what type of flame with a balance of oxygen and acetylene?
• Question #b9f95
• What family has the lowest ionization energy?
• Why is silicon an important element economically?
• When full, the innermost electron shell of argon contains how many electrons, and the outermost shell contains how many electrons?
• What is unique about each element of the periodic table?
• The sodium atom contains 11 electrons, 11 protons, and 12 neutrons. What is the mass number of sodium?
• Question #290b4
• In what period is carbon found?
• Helium was discovered on the sun in 1868, almost 30 years before it was discovered he on earth. How could that be possible?
• Copper is an element that is used in electrical wires. What is the smallest unit of copper that still maintains the characteristics of copper?
• What is the identity of zinc?
• If an element has too many or too few of what the element becomes unstable and will decay or not form at all?
• Which elements form diatomic molecules?
• What is the total charge of the nucleus of a nitrogen atom?
• How would you define pure substance? What are some examples of pure substances?
• What is one similarity and one difference between elements of group 2 and group 7?
• When carbon burns in oxygen what does it form?
• The element carbon is found naturally in several forms. What are some of these forms?
• Question #1ef00
• Of nitrogen, oxygen, and carbon dioxide, room temperature gases, which material is MOST involatile?
• What do all of the noble gases have?
• Build an atom using 4 protons, 5 neutrons, and 4 electrons. What element is it?
• How are sodium, chlorine, and aluminum alike?
• what is the difference between the reactivity and abundance of elements in Group 3A through Group 8A?
• What is the second major source of elements in seawater?
• How can I determine the color of iodide in a solution containing silver cation?
• How many neutrons are in calcium?
• What evidence is there (i) that sodium has a low melting point; that (ii) sodium is malleable and ductile?
• Question #c514a
• Which lanthanides are exceptions to the Aufbau principle?
• What is the only metal that is a liquid at room temperature?
• What is the hardest known material?
• What is the total number of protons and neutrons in the nuclide #""_35^80Br#?
• Which element in period 4 ls the most chemically active non-metal?
• What elements have melting and boiling points that are less than 10 °C (18 °F)?
• What did Uranium get its name from?
• Which elements are all highly reactive and are never found in Elemental forms in nature? Because of this, they are usually stored in mineral oil or kerosene (paraffin oil).
• Why is it dangerous to keep a sodium metal in your pocket?
• Why are the elements of group IA called alkali metals?
• Why is Cesium more reactive than Francium?
• Question #79959
• How will the density of mercury change when it is heated?
• Which gas is used to make blue prints?
• What are the basic units of matter that cannot be broken down into simpler substances by any chemical reaction called?
• Question #dac24
• How many protons, neutrons and electrons are in calcium?
• I do not uderstand the meaning of Eka - Boron . What is the meaning of Eka?
• For a given Period, which is the smallest atom?
• For which element(s) is/are the chemical symbols indicative of the element's americanized name?
• What is the electronic configuration of astatine?
• Why the lanthanide series is called lanthenide? Reason
• What elements are present in alkanes?
• Why actinides and lanthanides series are kept in the bottom of the periodic table? Reasons? Thank you.
• What is thallium 201?
• Why does phosphorus have a low melting point?
• Which is more stable vanadium or chromium? And why?
• Name a transition element which has no variable oxidation state?
• Question #e71de
• Question #7f389
• Are noble gases representative elements?
• Why d block elements are called outer transition and f block elements are called inner transition???? Please explain. Thanks a lot
• What is actual difference between atomic hydrogen and nascent hydrogen?
• Question #1d181
• What is the only element that can form both a cation and an anion?
• Question #c5ea9
• Why transition elements show tendency to form large number of complexes??
• Which element is named after one of our state?
• What are the allotropes of carbon?
• For the reaction #"Fe"_2"O"_3 + 2"X" -> 2"Fe" + "X"_2"O"_3#, if #"79.847 g"# #"Fe"_2"O"_3# reacts with excess #"X"# (#FW = "159.691 g/mol"# for the iron(III) oxide) to yield #"50.982 g X"_2"O"_3# and #"55.847 g Fe"#, what is the identity of #"X"#?
• First member of a group differs from the rest of the members of the same group. Why?
• What is the chemistry of the representative elements?
• An atom #a# possesses 30 massive, positively charged particles, and the atom #b# possesses 8 massive, positively charged particles. What are the identities of #a# and #b#?
• Are chromium, and copper isotopes?
• What are the reduction potentials of the halogens?
• Name and give symbol of the undiscovered element which have atomic number 119 by iupac method?
• What element has the chemical symbol Br?
• What is the chemical symbol for beryllium?
• Why is there no value for the covalent radius for argon?
• Of the known elements, how many are NON-METALS?
• Question #6548e
• What is the second most common element in the universe?
• I am the 2nd most abundant element in the Earth's crust and have 14 neutrons. What am I?
• Does selenium have more in common with sulfur or bromine?
• What element has never been made into a compound?
• What is the chemical symbol of phosphorus?
• How many protons are in a #""^179 Ta# nuclide?
• How many neutrons are in a #""^179 Ta# nuclide?
• Gold scientific name?