With what volume of 5.00 M HF will 4.72 g of calcium hydroxide react completely, according to the following reaction? 2HF + Ca (OH) 2 → CaF2 + 2H2O

The volume of 5.00 M HF that will react with 4.72 g of calcium hydroxide is 0.0256 L

calculation

2HF + Ca (OH) ₂ → CaF₂ + 2H₂O

Step 1: find the moles of Ca (OH) ₂

moles = mass: molar mass

from periodic table the molar mass of Ca (OH) ₂ = 40 + (16+1) ₂ = 74 g/mol

moles = 4.72 g: 74 g/mol = 0.0638 moles

Step 2: use the moles ratio to determine the moles of Hf

from the equation above HF: Ca (OH) ₂ is 2:1

therefore the moles of HF = 0.0638 moles x 2/1 = 0.1276 moles

Step 3: find the volume of HF

volume=moles / molarity

molarity = 5.00 M = 5.00 mol/L

=0.1276 moles / 5.00 mol/l = 0.0256 L