Question

В лаборатории имеется кристаллическая сода, но нет безводной. Для опыта экспериментатору потребовалось 100г раствора карбоната натрия с массовой долей 10,6%.Рассчитайте необходимые для приготовления данного раствора массы кристаллогидрата и объёма воды.Узнайте, какие вещества скрываются под перечисленными ниже бытовыми, техническими или историческими названиями веществ: гипс, глауберова соль, медный купорос, бура.

Answer 1

По идее, если массовая доля Na2CO3 - 10% а его требуется 100г, то потребуется 10,6 г Na2CO3 и  89,4 г воды

Гипс - CaSO4*2H2O

Глауберова соль - Na2SO4*10H2O

Медный купорос - CuSO4*5h2O

Бура - Na2B4O7*10H2O

Answer 2

Calculation of Mass of Crystalline Hydrate and Volume of Water

To calculate the mass of crystalline hydrate and the volume of water needed to prepare a 100g solution of sodium carbonate with a mass fraction of 10.6%, we need to use the following information:

- Mass of the solution (100g) - Mass fraction of sodium carbonate (10.6%)

Let's assume the mass of the crystalline hydrate is x grams and the mass of water is y grams.

The mass of sodium carbonate in the solution can be calculated as follows:

Mass of sodium carbonate = Mass of solution * Mass fraction of sodium carbonate

Substituting the given values:

Mass of sodium carbonate = 100g * 10.6%

To find the mass of the crystalline hydrate, we need to subtract the mass of sodium carbonate from the total mass of the solution:

Mass of crystalline hydrate = Mass of solution - Mass of sodium carbonate

Substituting the values:

Mass of crystalline hydrate = 100g - (100g * 10.6%)

To find the mass of water, we subtract the mass of the crystalline hydrate from the total mass of the solution:

Mass of water = Mass of solution - Mass of crystalline hydrate

Substituting the values:

Mass of water = 100g - (100g - (100g * 10.6%))

Now, let's calculate the values:

Mass of sodium carbonate = 100g * 10.6% = 10.6g

Mass of crystalline hydrate = 100g - (100g * 10.6%) = 89.4g

Mass of water = 100g - (100g - (100g * 10.6%)) = 10.6g

Therefore, to prepare a 100g solution of sodium carbonate with a mass fraction of 10.6%, you would need 89.4g of crystalline hydrate and 10.6g of water.

Identification of Substances

Let's identify the substances hidden behind the given names:

1. Гипс (Gypsum): Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate. It is commonly used in construction as a building material.

2. Глауберова соль (Glauber's Salt): Glauber's salt, also known as sodium sulfate decahydrate, is a white crystalline solid used in various industrial applications, including the manufacture of detergents and paper.

3. Медный купорос (Copper Sulfate): Copper sulfate is a blue crystalline compound that is used in agriculture as a fungicide and herbicide. It is also used in various chemical processes and as a laboratory reagent.

4. Бура (Borax): Borax, also known as sodium borate, is a white crystalline powder that is used in cleaning products, as a flux in metallurgy, and as a buffering agent in chemical laboratories.

Please note that the information provided above is based on general knowledge and may vary depending on specific contexts or applications.