Percent Mass

Based on the mass spectrum, which isotope of chlorine is most abundant?

• ³⁵Cl

• ³⁷Cl

• ⁷⁰Cl

• ⁷²Cl

How many isotopes of this element are shown in the mass spectrum?

• 98

• 7

• 100

• 95.9 g/mol

What is the percentage of chromium in K₂Cr₂O₇?

• 38.1%

• 27.2%

• 34.7%

• 100%

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

• 20%

• 27%

• 46%

• 53%

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

• 27.48% Mg

• 43.11% Mg

• 16.00% Mg

• 12.63% Mg

The mass % of H in methane (CH₄) is:

• 75%

• 92%

• 25%

• 4%

• 6%

What is the concentration, in percent by mass, of 0.62 g of solute in 45.0 g of solution?

• 0.014 %

• 1.4 %

• 0.13%

John is studying the composition of water for his science project. He needs to know the percent by mass of Oxygen in a water molecule (H₂O). Can you help him?

• 33 %

• 88.9%

• 11.1%

• 50%

Tags

NGSS.HS-ESS2-5

What is the percent by mass of Carbon in sugar C₁₂H₂₂O₁₁ ?

• 144.0

• 42.1

• 12.01

• 342.0

What is the percent by mass of Hydrogen in sugar C₁₂H₂₂O₁₁?

• 42.1

• 22.0

• 342.0

• 6.43