Percent Composition and Atomic Structure

What is the approximate percent by mass of magnesium in MgO?

• 20%
• 40%
• 50%
• 60%

What is the percent by mass of chlorine in NaCl?

• 39.2%

• 60.7%

• 35.1%

• 65.8%

Tags

NGSS.MS-PS1-1

What is the percent composition by mass of sulfur in the compound MgSO₄ ?

• 20%
• 27%
• 46%
• 53%

Tags

NGSS.HS-PS1-7

Find the percent composition of Cu₂S?

• 67.9%Cu 32.4%S

• 79.9%Cu  20.1%S

• 35.9%Cu  64.0%S

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

• 29%

• 43%

• 57%

• 73%

Tags

NGSS.MS-PS1-1

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

• 13.2%

• 43.2%

• 63.6%

• 87.0%

Tags

NGSS.MS-PS1-1

What approximate percentage of the total atomic mass of lithium phosphide (Li₃P) is composed of phosphorus?

• 13%

• 29%

• 40%

• 60%

Tags

NGSS.MS-PS1-1

What is the molar mass of NaOH?

• 39.997 g/mol

• 38.989 g/mol
• 23.998 g/mol
• 57.004 g/mol

What is the molar mass of KNO₃?

• 101.102 g/mol

• 85.978 g/mol

• 69.567 g/mol

• 48.265 g/mol

What is the molar mass of table salt (NaCl)?

• 116.886 g/mol
• 35.453 g/mol
• 22.990 g/mol
• 58.443 g/mol