5 grams of sodium was dissolved in water. determine the mass of the formed alkali and the volume of the evolved gas.
Sodium is an active alkali metal. Reacts violently with water to form sodium hydroxide and hydrogen gas. The equation for this reaction is as follows:
2 Na + 2 H2O = 2 NaOH + H2
The molar masses of the substances are as follows ?:
Sodium = 23 g / mol;
sodium hydroxide = 40 g / mol;
hydrogen = 2 g / mol.
According to the reaction equation, we will compose the proportion to find the mass of alkali.
5 g of sodium corresponds to X g of sodium hydroxide as
2 * 23 g / mol sodium corresponds to 2 * 40 g / mol sodium hydroxide
X = (5 * 2 * 40) / (2 * 23) = 8.7 g of sodium hydroxide
Now we will find the volume of the evolved hydrogen gas. Molar volume of gas = 22.4 L / mol
5 g of sodium corresponds to Y l. hydrogen like
2 * 23 g / mol sodium corresponds to 22.4 l / mol hydrogen
Y = 5 * 22.4 / (2 * 23) = 2.4 liters. hydrogen.
Answer: 8.7 g of sodium hydroxide and 2.4 liters. hydrogen.