Mass Percent

Find the percent composition of Cu₂S?

• %Cu= 67.987 %S= 32.013

• %Cu= 79.854   %S= 20.145

• %Cu= 35.946   %S= 64.054

Tags

NGSS.MS-PS1-1

What is the percent by mass of a solution made by dissolving 20.0 g of NaCl into 180.0 g of water?

• 10.0 %

• 11.1 %

• 80.0 %

• 20.0 %

Answer explanation

20g / (180g+ 20g) x 100 = 10 %

What is the percent by mass of a solution made by dissolving 10.0 g of NaCl into 180.0 g of water?

• 5.26 %

• 5.56 %

• 180.0 %

• 20.0 %

Answer explanation

10 g / (10 g + 180 g) x 100 = 5.26 %

What is the percent concentration of sugar in pink lemonade if 28 g of sugar is added to 209 g of water?

• 14.7 %

• 5.14 %

• 13.4 %

• 8.47 %

• 11.8 %

Answer explanation

28 g / ( 209g + 28g) x 100 = 11.8 %

What is the mass percent of oxygen in water (H2O)?

• 88.81%

• 33.33%

• 11.19%

• 50.00%

A solution is made by dissolving 5 g of salt in 95 g of water. What is the mass percent of salt in the solution?

• 5%

• 10%

• 15%

• 20%

Calculate the mass percent of carbon in carbon dioxide (CO2).

• 27.29%

• 72.71%

• 44.01%

• 12.01%

If 10 g of sugar is dissolved in 90 g of water, what is the mass percent of sugar in the solution?

• 10%

• 9%

• 11%

• 12%

What is the mass percent of hydrogen in methane (CH4)?

• 25.13%

• 74.87%

• 12.58%

• 87.42%

Tags

NGSS.MS-PS1-1

A 200 g solution contains 50 g of solute. What is the mass percent of the solute?

• 25%

• 20%

• 30%

• 40%