Answer to Question #136688 in General Chemistry for cindy

Question

When solutions of silver nitrate and calcium chloride are mixed, silver chloride precipitates out of solution according to the equation

2AgNO3(aq)+CaCl2(aq)→2AgCl(s)+Ca(NO3)2(aq)

How many moles are in 1.56 L of a 0.194 M solution of silver nitrate?

Answer 1

First, convert molarity to moles by multiplying by the volume:

0.194 M AgNO3 = (0.194 moles AgNO3)/1 L x 1.56 L = 0.3026 moles AgNO3

The banenced equestion is:

2AgNO3(aq)+CaCl2(aq)→2AgCl(s)+Ca(NO3)2(aq)

We are only interested in AgCl, not AgNO3. We convert moles of silver nitrate to moles of silver chloride using the balanced equation. This is a 2:2 conversion:

0.3026 moles AgNO3 reacts and produced

0.3026 moles AgNO3 x (2 mole AgCl)/(2 mole AgNO3) = 0.3026 moles AgCl

So 0.3026moles AgCl precipitated from

1.56 L of a 0.194 M solution of silver nitrate.