When sodium interacted with water, 5.6 liters of hydrogen were released. How many grams of sodium hydroxide was formed?

Let’s find the amount of the substance hydrogen.

V = Vn n, where Vn is the molar volume of the gas, equal to 22.4 l / mol, and n is the amount of substance.

n = V: Vn.

n = 5.6 L: 22.4 L / mol = 0.25 mol.

Let’s compose the reaction equation, find the quantitative ratios of substances.

2Na + 2H2O = 2NaOH + H2 ↑.

According to the reaction equation, there is 2 mol of sodium hydroxide for 1 mol of hydrogen. The substances are in quantitative ratios of 2: 1.

The amount of sodium hydroxide substance will be 2 times more than the amount of hydrogen substance.

n (NaOH) = 2n (H2) = 0.25 × 2 = 0.5 mol.

Find the mass of sodium hydroxide.

m = n × M.

M (NaOH) = 40 g / mol.

m = 40 g / mol × 0.5 mol = 20 g.

Answer: 20 g.



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