Question

Which contains the greatest mass of oxygen: 0.75 mol of ethanol (C2H5OH), 0.60 mol of formic acid (HCO2H) or 1.0 mol

of water (H2O) ?explain why.

Answer 1

formic acid

Step-by-step explanation:

(a) 0.75 moles of
`C_2H_5OH`

1 mole of
`C_2H_5OH` contains 1 mole of O

so,

0.75 moles of
`C_2H_5OH` contains 0.75 mole of O

Molar mass of O = 16 g/mol

Mass = moles* Molar mass = 0.75 moles × 16 g/mol = 12 g

(b) 0.60 moles of
`HCOOH`

1 mole of
`HCOOH` contains 2 moles of O

so,

0.60 moles of
`HCOOH` contains 0.60*2 mole of O

Moles of O = 1.2

Molar mass of O = 16 g/mol

Mass = moles* Molar mass = 1.2 moles × 16 g/mol = 19.2 g

(c) 1 mole of
`H_2O`

1 mole of
`H_2O` contains 1 mole of O

Molar mass of O = 16 g/mol

Mass = moles* Molar mass = 1 mole × 16 g/mol = 16 g

Greatest mass = 19.2 g = formic acid.