Percent Composition

Given the following: 42.07% Na, 18.89% P, and 39.04% O, determine the empirical formula.

•  NaPO2

• Na2PO3

• Na3PO4

• NaPO4

Find the percent composition of Cu₂S (molar mass 159.16 g/mol)?

• %Cu= 67.987 %S= 32.013

• %Cu= 79.854 %S= 20.145

• %Cu= 35.946 %S= 64.054

Find the percent composition of CaCl₂?

• Ca: 36.11%; Cl: 63.88%

• Ca: 53.12%; Cl: 100%

• Ca: 36.11%; Cl: 83.56%

• Ca: 46.11%; Cl: 63.88%

Tags

NGSS.HS-PS1-7

What is the percent by mass of magnesium in MgO?

• 20%

• 40%

• 50%

• 60%

What is the percent composition by mass of magnesium in the compound MgSO₄ (gram formula mass = 120 g/mol)?

• 20%

• 27%

• 46%

• 53%

What is the percent by mass of Cu in CuBr₂?

• 50%

• 71.6%

• 28.4%

• 44.3%

What is the percent by mass of chlorine in NaCl?

• 39%

• 61%

• 35%

• 65%

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%

Given the following: 42.07% Na, 18.89% P, and 39.04% O, determine the empirical formula.

• NaPO2

• Na2PO3

• Na3PO4

• NaPO4

• %Cu= 67.987 %S= 32.013

• %Cu= 79.854 %S= 20.145

• %Cu= 35.946 %S= 64.054