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• A 11.04g sample of a hydrocarbon produces 34.71g of CO2 and 14.20g H2O. What is empirical formula of hydrocarbon?
  
• How do you draw an atomic level diagram for 2S+3O2=2SO3 ?
  
• Why the number of atoms of bromine in 1 mole Br₂ is not equal to Avogadro's number?
  
• A substance has a molar mass of 40.0g/mol. If the decomposition of 1.00mole of this substance absorbs 60.0KJ of energy, how much energy would be absorbed by the decomposition of 20.0g of the substance?
  
• Write the balanced molecular equation for each reaction and the net ionic equation?
  
• Lisa wants to make an acid. She has two possible compounds she could add to 250.0 g of water to make this acid – EITHER 234.5 g of calcium oxide OR 678.9 g of tetraphosphorus decaoxide (she won’t use both, just one).? a. Which compound should s
  
• Aluminum + silver sulfide = ?
  
• 2Al+Zn(NO3)2=2Al(NO3)3+Zn net ionic equation?
  
• Using Rydberg's equation for the energy levels (E = -R/n^2) and the wavelength and the c=(lambda)v, E=hv equations, SHOW/ PROVE how E(red band in H-spectrum, lambda = 656 nm) = (Delta or change/ difference) E (3 --> 2)?
  
• Label the orbital with the following quantum numbers?
  
• Finding the empirical formula of iron oxide?
  
• Why bond polarity and molecular geometry determine molecular polarity?
  
• If a substance has very polar molecules, will the attraction between its molecules be stronger or weaker than the attraction between a substance with nonpolar molecules?
  
• Find the value of cos(inverse cot(tan(inverse sin(cos(inverse csc( 2radical3/3))))))?
  
• Find the value of cos(inverse cot(tan(inverse sin(cos(inverse csc( 2radical3/3))))))?
  
• What is the value of cot(arccot-3.2))?
  
• What is t he exact value of csc(arctan-1/3)) ?
  
• In general form, write the equation of the line that is perpendicular to y=12 and passes through the point(-5,8)?
  
• If line allb and line A has the equation 8x-6y+9=0, determine the equation of line b, in point-slope form if b passes (1,-2)?
  
• Why Br2 with Br2 has higher viscosity than HF with HF?
  
• Limiting reagent problem? For the reaction #C_2H_6+O_2 to CO_2+H_2O#
  
• Scientists estimate there are a million species that exist today, (yet/however) over 99% that ever existed are extinct. which is correct?
  
• Using the ideal gas formula, calculate the volume of 1.50 moles of a gas at 115 kPA and a temperature of 298K?
  
• Using boyle's law and your understanding of what is happening at the particle level, explain why the pressure increases in aclosed water bottle as you squeeze it?
  
• Using charles' law and understanding of what is happening at the particle level, explain why a marshmallow expands in size when you microwave it?
  
• Find the number of #"CO"_2# that exert a pressure of #"785 torr"# at a volume of #"32.5 L"# and a temperature #32^@"C"#?
  
• Using Graham's law of effusion, if #"CO"_2# takes 32 sec to effuse, how long will hydrogen take?
  
• At olympics? or In olympics?
  
• What is the domain and range of 3x-2/5x+1 and the domain and range of inverse of the function?
  
• If h(x) is given, find f(x) and g(x)? suppose h(x)=f(g(x)) h(x)=lx^2 -4l +3 f(x)= g(x)=
  
• The combination of coke and steam produces a mixture called coal gas, which can be used as a fuel or as a starting material for other reactions. If we assume coke can be represented by graphite, the equation for the production of coal gas is?
  
• If a reaction for the combustion of ethanol has a -29.7KJ/g, what is the molar heat of combustion?
  
• Write the reaction which has a heat of reaction equal to heat of formation for HCl(g) ?
  
• Sketch, find the end behavior(EB), y- int, zeros, and multiplicities?
  
• Mg(OH)2 has a solubility of 9.0x10^-5 M. What is the value of Ksp for Mg(OH)2?
  
• Would the solubility of #"Cu"_2"S"# increase, decrease or stay the same if #"AgNO"_3# is added to the solution?
  
• 6 moles of #"Cl"_2# are placed in a 3L flask at 1250K. At this temperature, #"Cl"_2# begins to dissociate into #"Cl"# atoms. What is the value for #K_c# if 50.0% of the #"Cl"_2# molecules dissociate when equilibrium has been achieved?
  
• Calculate the reaction quotient, #Q#, for mixing 100ml of 0.00028M #"Pb"("NO"_3)_2# with 200ml of 0.0012M #"NaCl"#. The #K_(sp)# for #"PbCl"_2# is #1.9 xx10^(-4)#. Does a precipitate form?
  
• Given the value of #K_(sp) = 2.9 xx 10^(-12)#, what would be the solubility of #"Mg"("OH")_2# in a 0.345 M #"NaOH"# solution?
  
• A mixture of 2.50mol H2, 1.5 mol CS2, 1.5 mol CH4 and 2mol H2S is placed in a 5.0L reaction vessel. When equilibrium is achieved, the concentration of CH4 has become 0.25M. Whay are the number of moles of CS2 at equilibrium?
  
• A 0.500M solution of a weak acid, HX, has a ka=3.26x10^-5 a) What is the pH of this solution? b) What is the percent ionization? c) What would be the pH be in a solution containing the strong electrolyte, 0.2M AlX3
  
• 358ml of an H3PO4 solution is completely titrated by 876mL of 0.0102M Ba(OH)2 solution?
  
• Is #"Ba"("OH")_2 + "H"_3"PO"_4 -> "BaHPO"_4 + 2"H"_2"O"# a possible reaction?
  
• Calculate the molarity of H3Po4 if 358ml of H3PO4 solution is completely titrated by 876ml of 0.0102M Ba(OH)2 solution? 2H3PO4+3Ba(OH)2= Ba3(PO4)2 +6H2O?
  
• Find, approximate, the area under f(x)=3x^2+6x +3 [-3,1] using the given partitions? a) 4 upper sum rectangles b) 2 midpoint rectangles c) 2 trapezoids d) 256 right sided rectangles
  
• Lim n approaches infinity# 6/n((2n)/3 + (5n(n+1))/(2n) - (4n(n+1)(2n+1))/(6n^2))=#?
  
• A shingle company manufactures premium grade shingles and high grade shingles using two common ingredients: asphalt and gravel. A batch of premium grade shingles requires 19 pounds of asphalt and 9 pounds of gravel and sells for $40 per batch. A batch of?
  
• For the linear system with augmented matrix shown below, find the REF and then solve the system by back substitution. (Do not do any row exchanges. And do not use the ref command on your calculator because the calculator uses row exchanges and will?
  
• For the linear system with augmented matrix shown below, find the REF and then solve the system by back substitution. (Do not do any row exchanges. And do not use the ref command on your calculator because the calculator uses row exchanges and will?
  
• Consider the system: 3x + 5y + 5z = −2 −3x + −1y + 0z = 7 −6x + 6y + 10z = k For what value of k is this system consistent?
  
• For what value of #k# is this system consistent? #3x + 5y + 5z = −2#, #−3x + −1y + 0z = 7# and #−6x + 6y + 10z = k#
  
• Consider the system: #{ (−2x_1 + 3x_2 + 4x_3 = a), (−4x_1 + 10x_2 + 12x_3 = b), (2x_1 + 9x_2 + 8x_3 = c) :}# What equation must #a#, #b# and #c# satisfy for this system to be consistent? (i.e. an equation like #5a − 3b + c = 0#)
  
• Consider the system? −3x + 5y + 3z = 0 6x + −7y + −4z = −2 9x + −6y + −3z = −6 Gaussian elimination of the augmented matrix for this system produces the matrix
  
• Consider the system? −3x + 5y + 3z = 0 6x + −7y + −4z = −2 9x + −6y + −3z = −6 Gaussian elimination of the augmented matrix for this system produces the matrix
  
• 3x + 5y + 5z = −2 −3x + −1y + 0z = 7 −6x + 6y + 10z = k For what value of k is this system consistent?
  
• In general, a linear equation in three variables x,y,z has the form Ax+By+Cz=D (where A,B,C,D are some constants) and geometrically corresponds to a plane in 3D. Graphically, the solution of a system of two linear equations in three variables CANNOT be?
  
• In general, a linear equation in three variables x,y,z has the form Ax+By+Cz=D (where A,B,C,D are some constants) and geometrically corresponds to a plane in 3D. Graphically, the solution of a system of two linear equations in three variables CANNOT be?
  
• In general, a linear equation in three variables x,y,z has the form Ax+By+Cz=D (where A,B,C,D are some constants) and geometrically corresponds to a plane in 3D. Graphically, the solution of a system of two linear equations in three variables CANNOT be?
  
• In general, a linear equation in three variables x,y,z has the form Ax+By+Cz=D (where A,B,C,D are some constants) and geometrically corresponds to a plane in 3D. Graphically, the solution of a system of two linear equations in three variables CANNOT be?
  
• A linear program is given by Maximize z = 60x1 + 60x2 + 36x3 Subject to 12x1 + 12x2 + 0x3 ≤ 72 30x1 + 18x2 + 18x3 ≤ 180 18x1 + 30x2 + 18x3 ≤ 180 x1 ≥ 0, x2 ≥ 0, x3 ≥ 0 For this linear program the maximum value of the objective function is z max? I
  
• A linear program is given by Maximize z = 60x1 + 60x2 + 36x3 Subject to 12x1 + 12x2 + 0x3 ≤ 72 30x1 + 18x2 + 18x3 ≤ 180 18x1 + 30x2 + 18x3 ≤ 180 x1 ≥ 0, x2 ≥ 0, x3 ≥ 0 For this linear program the maximum value of the objective function is z max= ? and it
  
• The product of two 2x3 matrices A2x3 and B2x3 is?
  
• The product of two 2x3 matrices A2x3 and B2x3 is?
  
• The product of two 2x3 matrices A2x3 and B2x3 is?
  
• A transition matrix T tells us how to get from one state to another. That is Sn=TSn-1, where Sn is the distribution vector at time n and Sn-1 is the distribution vector at time n-1. We can conclude? Sn=TSn/2 Sn=TS0 Sn=TnSn-1 Sn=TnS0
  
• Geometrically, the span of two non-parallel vectors in #R^3# is? one octant a line a point the whole 3-space a plane