Which contains the greatest mass of oxygen: 0.75 moles of ethanol (C2H5OH), 0.60 mole of formic acid (HCO2H), or 1.0 mole of water (H2O) ? Why?

0.60 mole of formic acid contains the greatest mass of oxygen

(19.2 grams)

Explanation:

Step 1: Data given

Moles of ethanol = 0.75 moles

Molar mass ethanol = 46.07 g/mol

Moles of formic acid = 0.60 moles

Molar mass of formic acid = 46.03 g/mol

Moles of H2O = 1.0

Molar mass of H2O = 18.02 g/mol

Step 2: Calculate moles of oxygen in each

Ethanol: For 1 mol ethanol we have 1 mol oxygen

For 0.75 moles ethanol we have 0.75 moles O

Mass O = 0.75 moles * 16.0 g/mol = 12.0 grams O

Formic acid: For 1 mol formic acid, we have 2 moles O

For 0.60 moles formic acid, we have 2*0.60 = 1.20 moles O

Mass O = 1.20 moles * 16.0 g/mol = 19.2 grams O

H2O: for 1.0 mol H2O we have 1 mol O

Mass O = 18.02 g/mol * 1.0 mol = 18.02 grams

0.60 mole of formic acid contains the greatest mass of oxygen

(19.2 grams)

In conclussion, 0.60 moles of HCOOH contains the greatest mass of O

Explanation:

Let's make some rules of three, to solve this problem:

1 mol of ethanol has 2 moles of C, 6 moles of H, and 1 mol of oxygen

Therefore, 0.75 moles of ethanol must have 0.75 mol of oyxgen

Let's convert the moles to mass → 0.75 mol. 16 g / 1 mol = 12 g

1 mol of formic acid has 2 moles of H, 1 mol of C and 2 mol of oxygen

0.60 moles of formic acid must have (0.6.2) / 1 = 1.2 mol of O

If we convert the amount to mass → 1.2 mol. 16 g / 1mol = 19.2 g

1 mol of water has 1 mol of oyxgen

Therefore, we have 1 mol of oxygen with a mass of 16 g.

In conclussion, 0.60 moles of HCOOH contains the greatest mass of O