Step 1
Molarity is defined as follows:
[tex]Molarity\text{ \lparen M or mol/L\rparen = }\frac{Number\text{ of moles of HCl}}{Volume\text{ of solution \lparen L\rparen}}[/tex](L) means liters.
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Step 2
Information needed:
11.5 mL of 0.14 M HCl
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Information needed:
The molar mass of HCl = 36.5 g/mol (please, the periodic table is useful here)
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Step 3
From step 1, the number of moles, n, is found as follows:
(1 L = 1000 mL), so 11.5 mL x (1 L/1000 mL) = 0.0115 L
Molarity = number of moles/volume
Molarity x volume = number of moles = n
0.14 mol/L x 0.0115 L = n
1.61x10^-3 moles = n
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Now,
n = mass/molar mass
n x molar mass = mass
1.61x10^-3 moles x 36.5 g/mol = mass
0.059 g = mass of HCl
Answer: 0.059 g of HCl
