Question

Given the following solution, 50.00 mL 0.10M Potassium Chlorate, K2CrO4 answer the following.

1) What volume(mL) of the solution contains 5.00 x 10^-4 miles of the solute?

2) What volume of the solution contains 1.00 g of the solute?

3) What is the new molarity of a solution made by pipeting 5.00 mL of the solution and diluting with 95.00 mL of deionized water?

4) What volume of the solution is required to react with 10.00 mL of 0.10M Pb(NO3)2?

Please show work!!!

Answer 1

Given the following solution, 50.00 mL 0.10M Potassium Chlorate, K2CrO4 answer the following.

1) What volume (mL) of the solution contains 5.00 x 10^-4 miles of the solute?

Molarity = number of moles /volume in L

Volume in L = number of moles / molarity

= 5.00 x 10^-4 moles */ 0.10 moles / L

= 5.00 x 10^-5 L

= 0.05 ml

2) What volume of the solution contains 1.00 g of the solute?

Mole of solute – amount in g/ molar mass

= 1.00 g/ 194.19 g/ mole

= 5.15*10^-3 moles

Molarity = number of moles /volume in L

Volume in L = number of moles / molarity

= 5.15*10^-3 moles/ 0.10 moles / L

= 0.0515 L

= 51.5 ml

3) What is the new molarity of a solution made by pipeting 5.00 mL of the solution and diluting with 95.00 mL of deionized water?

M1V1 = M2V2

Here M1 =0.10 M

V1 = 5.00 ml

M2= ?

V2= 95.00 ml

0.10*5.00 = M2* 95.00

M2 = 5.29*10^-3 M

4) What volume of the solution is required to react with 10.00 mL of 0.10M Pb(NO3)2?

K2CrO4 + Pb(NO3)2 -> PbCrO4(s) + 2KNO3

The moles of Pb(NO3)2;

Number of moles = molarity * volume in L

= 0.10 moles / L * 0.010 L

= 0.001 moles

According to reaction the number of moles of K2CrO4 are 0.001 moles

Volume in L = number of moles / molarity

= 0.001 moles/ 0.10 moles / L

= 0.01 L

= 10.0 ml