PLS HELP.

Chemistry

1 answer:

Lesechka [4]2 years ago

6 0

Answer:

1. 57.5%

2. 27.89 g

Explanation:

1. Determination of the percentage of sodium in sodium hydroxide.

Molar mass of NaOH = 23 + 16 + 1 = 40 g/mol

Mass of Na in NaOH = 23 g

Percentage of Na = mass of Na / Molar mass of NaOH × 100

Percentage of Na = 23/40 × 100

Percentage of Na = 57.5%

2. Determination of the mass of sodium in 48.5 g of sodium hydroxide.

Molar mass of NaOH = 23 + 16 + 1 = 40 g/mol

Mass of Na in NaOH = 23 g

Total mass of NaOH = 48.5 g

Mass composition of Na = mass of Na / Molar mass of NaOH × Total mass

Mass composition of Na = 23/40 × 48.5

Mass composition of Na = 27.89 g

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