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1.

The molar mass of sodium hydroxide NaOH is

40 g/mol

39 g/mol

24 g/mol

56 g/mol

2.

The number of moles in 36 g of water is

0.5 mol

1 mol

2 mol

4 mol

3.

Which sample contains the greatest number of atoms?

1 mol of H₂O

1 mol of CO₂

1 mol of NH₃

1 mol of CH₄

4.

The number of ions produced when 0.1 mol of CaCl₂ dissolves completely in water is

1.806 × 10²³

6.02 × 10²²

1.204 × 10²³

3.01 × 10²³

5.

2Na + 2H₂O → 2NaOH + H₂. The mass of sodium that releases 1.12 L of hydrogen at STP is

1.15 g

2.3 g

4.6 g

0.23 g

6.

The mass of carbon contained in 22 g of CO₂ is

12 g

6 g

3 g

22 g

Question bank: Chapter 1 — Chemical Calculation