yr 11 mole revision 2023

Which of the following describes 6.02 x 10²³ particles?

• 10 g NaOH

• 32 g O₂

• 9 g H₂O

• 55 g HCl

the % by mass of Mg in magnesium sulfate is

• 11.2 %

• 20.2 %

• 33.6 %

• 79.5 %

An organic compound consists of 54.5% C, 9.1% H and the rest as O. The empirical formula is

• C₂H₄O

• CHO

• C₂H₃O

• C₄H₈O₂

A sample of Al₂(SO₄)₃ contains 0.50 mol Al3+ ions. The mass of oxygen in the sample is

• 8 g

• 16 g

• 48 g

• 96 g

Which of the following has the smallest number of mole of nitrogen atoms?

• 1.4 mol sodium nitrate (NaNO₃)

• 5.0 x 10²³ molecules of N₂O

• 1.2 x 10²⁴ atoms of nitrogen (N)

• 22 g of nitrogen gas (N₂)

The molar mass of barium hydroxide is

• 154.3

• 154.3 g/mol

• 171.3

• 171.3 g/mol

The mass of 0.20 mol of a substance is 12.8 g. The identity of the substance could be

• KCl

• SiH₄

• O₂

• SO₂

Which pair consists of a molecular formula and its corresponding empirical formula?

• C₂H₂ and CH₃CH₃

• P₄O₁₀ and P₂O₅

• C₆H₆ and C₂H₂

• SO₂ and SO₃

Which has the greatest mass?

• 4 mol of oxygen atoms (O)

• 6 x 10²⁵ atoms of He

• 200 g of iron (Fe)

• 6 x 10²⁵ molecules of H₂

Calculate the percentage of composition by mass of oxygen in Al(HCO₃)₃.

• 22.86 %

• 68.57 %

• 78.26 %

• 40.50 %