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Honors Chemistry Name _______________________
Concentrations of Solutions Date ________________________
Complete the following problems on a separate sheet of paper. Use significant figures.
Note: The density of water is 1 g/mL.
1. What is the molarity of a solution that contains 10.0 grams of Silver Nitrate that has been
dissolved in 750 mL of water?
10.0!𝑔!𝐴𝑔𝑁𝑂!
1
!𝑥!
1!𝑚𝑜𝑙𝑒!𝐴𝑔𝑁𝑂!
169.872!𝑔!𝐴𝑔𝑁𝑂!
=!0.0588678!𝑚𝑜𝑙𝑒𝑠!𝐴𝑔𝑁𝑂!
𝑀=!
𝑛
𝑉!(𝑖𝑛!𝐿)!=!
0.0588678!𝑚𝑜𝑙𝑒𝑠!𝐴𝑔𝑁𝑂!
0.75!𝐿
=0.078!𝑀!𝐴𝑔𝑁𝑂!
2. You want to create a 0.25 M Potassium Chloride solution. You mass 5.00 grams of Potassium
Chloride. How much water is needed?
5.00!𝑔!𝐾𝐶𝑙
1
!𝑥!
1!𝑚𝑜𝑙𝑒!𝐾𝐶𝑙
74.551!𝑔!𝐾𝐶𝑙 =0.067068!𝑚𝑜𝑙𝑒𝑠!𝐾𝐶𝑙
!𝑀=!
𝑛
𝑉
−𝑠𝑜𝑙𝑣𝑒!𝑓𝑜𝑟!𝑣𝑜𝑙𝑢𝑚𝑒
𝑉=!
𝑛
𝑀
=!
0.067068!𝑚𝑜𝑙𝑒𝑠!𝐾𝐶𝑙
0.25!𝑀!𝐾𝐶𝑙 =0.27!𝐿=270!𝑚𝐿
3. What is the molality of a solution that contains 48 grams of sodium chloride and 250 mL of
water?
48!𝑔!𝑁𝑎𝐶𝑙
1
!𝑥!
1!𝑚𝑜𝑙𝑒!𝑁𝑎𝐶𝑙
58.443!𝑔!𝑁𝑎𝐶𝑙 =!0.8213!𝑚𝑜𝑙𝑒𝑠!𝑁𝑎𝐶𝑙
250!𝑚𝐿!𝐻!𝑂
1
!𝑥!
1!𝑔!𝐻!𝑂
1!𝑚𝐿!𝐻!𝑂
!𝑥!
1!𝑘𝑔!𝐻!𝑂
1000!𝑔!𝐻!𝑂
=!0.25!𝑘𝑔!𝐻!𝑂
𝑚𝑜𝑙𝑎𝑙𝑖𝑡𝑦 =!
𝑚𝑜𝑙𝑒𝑠!𝑠𝑜𝑙𝑢𝑡𝑒
𝑘𝑔!𝑠𝑜𝑙𝑣𝑒𝑛𝑡 =!
0.8213!𝑚𝑜𝑙𝑒𝑠!𝑁𝑎𝐶𝑙
0.25!𝑘𝑔!𝐻!𝑂
=3.3!𝑚!𝑁𝑎𝐶𝑙
4. What is the percentage by mass of the solution from problem 1?
750!𝑚𝐿!𝐻!𝑂
1
!𝑥!
1!𝑔!𝐻!𝑂
1!𝑚𝐿!𝐻!𝑂
=!750!𝑔!𝐻!𝑂
𝑃𝑒𝑟𝑐𝑒𝑛𝑡!𝑏𝑦!𝑀𝑎𝑠𝑠 =!
𝑚𝑎𝑠𝑠!𝑜𝑓!𝑠𝑜𝑙𝑢𝑡𝑒
𝑚𝑎𝑠𝑠!𝑜𝑓!𝑠𝑜𝑙𝑢𝑡𝑖𝑜𝑛 !𝑥!100 =!
10.0!𝑔!𝐴𝑔𝑁𝑂!
10.0!𝑔+750!𝑔
!𝑋!100 =1.32!!𝐴𝑔𝑁𝑂!
5. How many mL of hydrogen peroxide are needed to make a 8.5% solution by volume of hydrogen
peroxide if you want to make 450 mL of solution?
𝑃𝑒𝑟𝑐𝑒𝑛𝑡!𝑉𝑜𝑙𝑢𝑚𝑒 =!
𝑣𝑜𝑙𝑢𝑚𝑒!𝑜𝑓!𝑠𝑜𝑙𝑢𝑡𝑒
𝑣𝑜𝑙𝑢𝑚𝑒!𝑠𝑜𝑙𝑢𝑡𝑖𝑜𝑛 !𝑥!100
