Question #dc377

1 Answer
Jan 14, 2014

There is none.

A mole ratio or molar ratio a fraction made up from the coefficients in a balanced equation. It is used to convert the number of moles of one substance to number of moles of another substance.

Therefore, you need a balanced equation involving KC₂H₃O₂ and something else. For example, in the equation

2KC₂H₃O₂ + H₂SO₄ → 2HC₂H₃O₂ + K₂SO₄

you can have the following molar ratios involving KC₂H₃O₂:

#(2 mol KC₂H₃O₂)/(1 mol H₂SO₄)#; #(2 mol KC₂H₃O₂)/(2 mol HC₂H₃O₂)#; #(2 mol KC₂H₃O₂)/(1 mol K₂SO₄)#;

#(1 mol H₂SO₄)/(2 mol KC₂H₃O₂)#; #(2 mol HC₂H₃O₂)/(2 mol KC₂H₃O₂)#; and #(2 mol K₂SO₄)/(2 mol KC₂H₃O₂)#

EXAMPLE 1:

What is the mole ratio between KC₂H₃O₂ and H₂SO₄ in the above reaction?

Answer:

The mole ratio is either #(2 mol KC₂H₃O₂)/(1 mol H₂SO₄)# or #(1 mol H₂SO₄)/(2 mol KC₂H₃O₂)#

We pick the fraction that gives us the correct units in a particular problem.

EXAMPLE 2:

Use the above equation to determine the number of moles of HC₂H₃O₂ that can be prepared using 0.24 mol KC₂H₃O₂.

Answer:

The mole ratio is either #(2 mol KC₂H₃O₂)/(2 mol HC₂H₃O₂)# or #(2 mol HC₂H₃O₂)/(2 mol KC₂H₃O₂)#.

We choose the one that makes the units cancel and give the correct units for the answer — the second one.

0.24 mol KC₂H₃O₂ × #(2 mol HC₂H₃O₂)/(2 mol KC₂H₃O₂)# = 0.24 mol HC₂H₃O₂