Question #9e3a5

1 Answer
Nov 22, 2017

Working from the following metathesis reaction ...

2HNO_3(aq) + Ca(OH)_2(aq) => Ca(NO_3)_2 + 2H_2O(l)

The reaction ratio to neutralization is 2 moles HNO_3 to 1 mole Ca(OH)_2

From definition of
"Molarity"(M) = ("moles"."solute")/("Liters"."solution")

=> "moles"."solute"= "Molarity(M)"xx"Volume(L)"

Therefore, one can use the relationship

1 mole HNO_3 = 2 moles Ca(OH)_2

(Molarity x Volume)HNO_3 = 2(Molarity x Volume)Ca(OH)_2

(0.177M)HNO_3(aq) xx(28.2ml)HNO_3 "solution") = 2[Ca(OH)_2(aq)] xx(17.5ml)Ca(OH)_2 "solution")

Simplifying notations for illustration

(0.177M)(28.2ml) = 2[Ca(OH)_2(aq)](17.5ml)

[Ca(OH)_2] = ((2(0.177M)(28.2ml))/(17.5ml))

= 0.570M Ca(OH)_2(aq) "solution"

Note: In this problem case, the volume values may remain in milliliter dimensions as both sides of the (MV)acid = (MV)base are in ml's.