Through a solution containing 10 g of sodium hydroxide, passed 20 g of hydrogen sulfide.

| June 17, 2021 | education

Through a solution containing 10 g of sodium hydroxide, passed 20 g of hydrogen sulfide. What kind of salt and in what quantity do you get it?

1) This is a problem for “excess – lack”. For its correct solution, it is necessary to determine which of the reagents was taken in the deficiency – caustic soda or hydrogen sulfide:

2NaOH + H2S -> Na2S + 2H2O.

According to the formula: amount of a substance = mass of a substance: molar mass of a substance.

The amount of NaOH = 10: 40 = 0.25 mol.

H2S amount = 20: 34 = 0.588 mol.

According to the reaction equation, 1 mol of hydrogen sulfide is needed for 2 mol of NaOH, which means that 0.25 mol of hydroxide will react with 0.5 mol of gas. We have as much as 0.588 mol of hydrogen sulfide.

So “in short supply” – caustic soda and then we will calculate by its mass.

2) Find the mass of the resulting salt (sodium sulfide):

2NaOH + H2S -> Na2S + 2H2O.

x = 10 * 78: 2 * 40 = 9.75 (g).



One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.