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Name Date SOLUTIONS Classwork Ch.6 1. Calculate the mass/volume percent composit

ID: 693366 • Letter: N

Question

Name Date SOLUTIONS Classwork Ch.6 1. Calculate the mass/volume percent composition, or % (msv), of 0.300 L of solution containing 15.0g of glucose. 2. Calculate the % (mw) of 0.0600 L of solution containing 10.0g NaCl 3. Calculate the % (mn) of 0.200 L of solution containing 15.0 g KCI 4. Calculate the number of g of NaCl in 5.00 X 102 mL of a 10.0 % (mV) solution. 5. Calculate the mass (in g) of sodium hydroxide required to make 2.00 L of a 1.00% (m/V) solution. 6. Calculate the volume (in mL) of a 25.0% (mV) solution containing 10.0g Naci 7. Calculate the % (m/m) of platinum in a gold ring that contains 14.00g gold and 4.500g platinum S. A 1.00g sample of stream water was found to contain 1.0 x 10'g lead. Calculate the concentration of lead in the stream water in units of % (mm), ppt, and ppm, which is the most suitable unit? Calculate the ppt and ppm of oxygen gas in a mixture containing 20.0g of oxygen gas and 80.0g of nitrogen gas. 9. 10. Calculate the ppt and ppm of argon gas in a mixture containing 50.0g of argon gas and 80.0g of helium gas.

Explanation / Answer

1. %(m/v) = (mass of solute/volume of solution) x 100

15 g glucose in 0.3 L (300 ml) solution

%(m/v) = (15/300) x 100 = 5%

2. 10 g NaCl in 0.06 L (60 ml)

%(m/v) = (10/60) x 100 = 16.7%

3. 15 g KCl in 0.2 L (200 ml)

%(m/v) = (15/200) x 100 = 7.5%

4. 10%(m/v) = 10 g in 100 ml

So,

in 5 x 10^2 ml,

mass of NaCl = 0.1 x 5 x 10^2 = 50 g NaCl

5. 1%(m/v) = 1 g in 100 ml

for 2 L = 2000 ml,

we need = 0.01 x 200 = 20 g NaOH

6. 25%(m/v) = 10 g NaCl/volume of solution

Volume of solution = 10 x 100/25 = 40 ml

7. %(m/m) Pt in Au

Pt = 4.5 g

Au = 14 g

total = 18.5 g

%(m/m) = 4.5 g x 100/18.5 g = 24.32%