what mass of H2O can be produced?

Question

Given the equation below, 12.35 grams of H₂SO₄, and excess Ca(OH)₂, what mass of H₂O can be produced? Round your answer to two digits after the decimal point.

H₂SO₄ + Ca(OH)₂ à 2 H₂O + CaSO₄

Answer 1

Step 1) Convert 12.35 grams of H₂SO₄ into moles of H₂SO₄ by first calculating the molar mass of H₂SO₄:

Hydrogen: 1.008 x 2 = 2.016 g/mol

Sulfur: 32.066 x 1 = 32.066 g/mol

Oxygen: 15.999 x 4 = 63.996 g/mol

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98.078 g/mol

(12.35 g)/(98.078 g/mol) = 0.12592 moles

Step 2) Convert moles of H₂SO₄ into moles of H₂O

Using the balanced chemical reaction equation:

H₂SO₄ + Ca(OH)₂ → 2H₂O + CaSO₄ we can see that for every 1 moles of H₂SO₄ there are 2 moles of H₂O produced so if we start with 0.12592 moles of H₂SO₄, we will produced double that, or 0.25184 moles of H₂O.

Step 3) Convert moles of H₂O into grams of H₂O by first calculating the molar mass of H₂O:

Hydrogen: 1.008 x 2 = 2.016 g/mol

Oxygen: 15.999 x 1 = 15.999 g/mol

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18.015 g/mol

( 0.25184 moles)(18.015 g/mol) = 4.54 grams