213k views
3 votes
Question List (4 items) (Drag and drop into the appropriate area) Find the volume of HCl that will neutralize the base. Find the mass (in grams) of Ca(OH)2. Calculate the number of moles of Ca(OH)2. Calculate the number of moles of H required to neutralize the base.

User Ouroborus
by
5.0k points

1 Answer

0 votes

The question is incomplete, the complete question is:

The solubility of slaked lime,
Ca(OH)_2, in water is 0.185 g/100 ml. You will need to calculate the volume of
2.50* 10^(-3)M HCl needed to neutralize 14.5 mL of a saturated

Answer: The volume of HCl required is 290mL, the mass of
Ca(OH)_2 is 0.0268g, the moles of

Step-by-step explanation:

Given values:

Solubility of
Ca(OH)_2 = 0.185 g/100 mL

Volume of
Ca(OH)_2 = 14.5 mL

Using unitary method:

In 100 mL, the mass of
Ca(OH)_2 present is 0.185 g

So, in 14.5mL. the mass of
Ca(OH)_2 present will be =
(0.185)/(100)* 14.5=0.0268g

The number of moles is defined as the ratio of the mass of a substance to its molar mass.

The equation used is:


\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}} ......(1)

Given mass of
Ca(OH)_2 = 0.0268 g

Molar mass of
Ca(OH)_2 = 74 g/mol

Plugging values in equation 1:


\text{Moles of }Ca(OH)_2=(0.0268g)/(74g/mol)=0.000362 mol

Moles of
OH^- present =
(2* 0.000362)=0.000724mol

The chemical equation for the neutralization of calcium hydroxide and HCl follows:


Ca(OH)_2+2HCl\rightarrow CaCl_2+2H_2O

By the stoichiometry of the reaction:

Moles of
OH^- = Moles of
H^+ = 0.000724 mol

The formula used to calculate molarity:


\text{Molarity of solution}=\frac{\text{Moles of solute}* 1000}{\text{Volume of solution (mL)}} .....(2)

Moles of HCl = 0.000724 mol

Molarity of HCl =
2.50* 10^(-3)

Putting values in equation 2, we get:


2.50* 10^(-3)mol=\frac{0.000724* 1000}{\text{Volume of solution}}\\\\\text{Volume of solution}=(0.000725* 1000)/(2.50* 10^(-3))=290mL

Hence, the volume of HCl required is 290mL, the mass of
Ca(OH)_2 is 0.0268g, the moles of

User Arletty
by
4.9k points