percent composition

What is the percent by mass of oxygen in MgO?

• 20%
• 40%
• 50%
• 60%

What is the percent by mass of sodium in NaCl?

• 39%
• 61%
• 35%
• 65%

What percentage of the total atomic mass of carbon monoxide (CO) is composed of carbon?

• 29%

• 43%

• 57%

• 73%

What percentage of the total atomic mass of magnesium bromide (MgBr₂) is composed of magnesium?

• 13%

• 43%

• 63%

• 87%

What is the percent composition of benzene, C₆H₆?

• C = 50.%

  H = 50.%

• C = 85.7 %

  H = 14.3%

• C = 92.2%

  H = 7.8%

• C = 71.9%

  H = 28.1%

Find the percent composition of Cu₂S?

• %Cu= 67.987 %S= 32.013
• %Cu= 79.854   %S= 20.145
• %Cu= 35.946   %S= 64.054

Find the percentage composition of Mg in Mg₃(PO₄)₂.

• 27.48% Mg

• 43.11% Mg

• 16.00% Mg

• 12.63% Mg

What is the mass percentage of Carbon in Carbon dioxide (CO₂)?

• 27.27%

• 42.86%

• 72.73%

• 72.72%