What a V hydrogen image. When dissolved in water, an alloy containing 6.9 grams of sodium and 7.8 grams of potassium.

Potassium and sodium are active alkali metals. They interact with water actively with the formation of alkalis and the evolution of hydrogen. Let us find in turn the volume of hydrogen in each reaction. Molar volume of hydrogen at normal conditions is equal to 22.4 l / mol.

Let’s find the hydrogen released during the reaction of sodium with water.

2 Na + 2 H2O = 2 NaOH + H2

The molar mass of sodium is 23 g / mol.

Let’s make a proportion according to the equation:

6.9 g of sodium correspond to X l. hydrogen like

2 * 23 g / mol of sodium corresponds to 22.4 l / mol of hydrogen.

X = (6.9 * 22.4) / (2 * 23) = 3.36 liters.

Potassium reacts with water in a similar way:

2 K + 2 H2O = 2 KOH + H2

The molar mass of potassium is 39 g / mol.

According to the reaction equation, we compose the proportion:

7.8 g of potassium corresponds to Y l. hydrogen like

2 * 39 g / mol of potassium corresponds to 22.4 l / mol of hydrogen.

Y = (7.8 * 22.4) / (2 * 39) = 2.24 l.

Let’s find the total volume of hydrogen released in both reactions:

V = X + Y = 3.36 + 2.24 = 5.6 l.

Answer: the volume of hydrogen is 5.6 liters.