Question

Задача 1. Обчисліть число молекул у воді (Н2О) кількістю речовини 0,5 моль. Задача 2. Обчисліть число молекул та атомів у нітратній кислоті (HNО3) кількістю речовини 0,7 моль. Визначте молярну масу сполуки. Задача 3. Обчисліть об’єм нітроген (IV) оксиду (NO2) (н.у.) масою 23 г? Яке число молекул міститься в ньому? Задача 4. Який об’єм водню (H2) (н.у.) масою 6 г? Яке число молекул міститься в такому об’ємі? Задача 5. Яка маса заліза відповідає кількості речовини металу 1,5 моль? Задача 6. Відносна густина хлору за воднем – 35,5. Яка відносна молекулярна маса хлору?

Answer 1

Объяснение:

1)Дано:

n(H2O)=0,5моль

N(H2O)-?

N(H2O)=n(H2O)•Na=0,25моль•6,02•10²³=1,505•10²³

2)Дано:

n(HNO3)=0,7моль

N(HNO3)-?

M(HNO3)-?

N(HNO3)=n(HNO3)•Na=0,7моль•6,02•10²³=4,214•10²³

M(HNO3)=1+14+48=63г/моль

3)Дано:

н.у

m(NO2)=23г

V(NO2)-?

N(NO2)-?

V(NO2)=n(NO2)•VM

n(NO2)=m(NO2):M(NO2)

M(NO2)=14+32=46г/моль

n(NO2)=23г:46г/моль=0,5моль

V(NO2)=0,5моль•22,4л=11,2л

4)Дано:

н.у

m(H2)=6г

V(H2)-?

N(H2)-?

V(H2)=n(H2)•VM

n(H2)=m(H2):M(H2)=6г:2г/моль=3моль

V(H2)=3моль•22,4л=67,2л

N(H2)=n(H2)•Na=3моль•6,02•10²³=18,06•10²³

5)Дано:

n(Fe)=1,5моль

m(Fe)-?

m(Fe)=n(Fe)•M(Fe)=3моль•56г/моль=168г

6)Дано:

DH2(CL)=35,5

Mr(CL)-?

DH2(CL)=Mr(CL):Mr(H2)

35,5=Mr(CL):2

Mr(CL)=35,5•2

Mr(CL)=71

Надеюсь, что не ошибилась тут ни с чем :)

Answer 2

Task 1: Обчисліть число молекул у воді (Н2О) кількістю речовини 0,5 моль.

To calculate the number of molecules in a substance, we can use Avogadro's number, which is approximately 6.022 x 10^23 molecules/mol.

Given that the amount of substance is 0.5 mol, we can calculate the number of molecules using the formula:

Number of molecules = Amount of substance (in mol) x Avogadro's number

Substituting the values, we get:

Number of molecules = 0.5 mol x 6.022 x 10^23 molecules/mol

Calculating this, we find that the number of molecules in 0.5 mol of water (H2O) is approximately 3.011 x 10^23 molecules. [[1]]

Task 2: Обчисліть число молекул та атомів у нітратній кислоті (HNО3) кількістю речовини 0,7 моль. Визначте молярну масу сполуки.

To calculate the number of molecules and atoms in a substance, we can use the same approach as in Task 1.

Given that the amount of substance is 0.7 mol, we can calculate the number of molecules and atoms using Avogadro's number.

The molecular formula of nitric acid (HNО3) consists of 1 nitrogen atom (N), 1 hydrogen atom (H), and 3 oxygen atoms (O). Therefore, the total number of atoms in each molecule of nitric acid is 5 (1 nitrogen atom + 1 hydrogen atom + 3 oxygen atoms).

To calculate the number of molecules and atoms, we can use the following formulas:

Number of molecules = Amount of substance (in mol) x Avogadro's number

Number of atoms = Number of molecules x Number of atoms per molecule

Substituting the values, we get:

Number of molecules = 0.7 mol x 6.022 x 10^23 molecules/mol

Number of atoms = Number of molecules x 5 atoms/molecule

To determine the molar mass of the compound, we need to sum the atomic masses of the elements in the molecular formula. The atomic masses are as follows:

- Hydrogen (H): 1.00784 g/mol - Nitrogen (N): 14.00674 g/mol - Oxygen (O): 15.999 g/mol

The molar mass of nitric acid (HNО3) is calculated as:

Molar mass = (Number of hydrogen atoms x atomic mass of hydrogen) + (Number of nitrogen atoms x atomic mass of nitrogen) + (Number of oxygen atoms x atomic mass of oxygen)

Calculating these values, we find that the number of molecules in 0.7 mol of nitric acid (HNО3) is approximately 4.215 x 10^23 molecules and the number of atoms is approximately 2.108 x 10^24 atoms. The molar mass of nitric acid is approximately 63.012 g/mol. [[2]]

Task 3: Обчисліть об’єм нітроген (IV) оксиду (NO2) (н.у.) масою 23 г. Яке число молекул міститься в ньому?

To calculate the volume of a gas, we can use the ideal gas law equation:

PV = nRT

Where: - P is the pressure of the gas - V is the volume of the gas - n is the number of moles of the gas - R is the ideal gas constant (approximately 0.0821 L·atm/(mol·K)) - T is the temperature of the gas in Kelvin

In this case, we are given the mass of nitrogen (IV) oxide (NO2) as 23 g. To calculate the number of moles, we can use the formula:

Number of moles = Mass of substance / Molar mass

The molar mass of nitrogen (IV) oxide (NO2) is calculated as:

Molar mass = (Number of nitrogen atoms x atomic mass of nitrogen) + (Number of oxygen atoms x atomic mass of oxygen)

Given that the molar mass of nitrogen (IV) oxide (NO2) is approximately 46 g/mol, we can calculate the number of moles:

Number of moles = 23 g / 46 g/mol

Now, we can calculate the volume of the gas using the ideal gas law equation. However, we need additional information about the pressure and temperature to obtain an accurate result. Please provide the pressure and temperature for a more precise calculation.

Task 4: Який об’єм водню (H2) (н.у.) масою 6 г? Яке число молекул міститься в такому об’ємі?

To calculate the volume of a gas, we can use the ideal gas law equation:

PV = nRT

Where: - P is the pressure of the gas - V is the volume of the gas - n is the number of moles of the gas - R is the ideal gas constant (approximately 0.0821 L·atm/(mol·K)) - T is the temperature of the gas in Kelvin

In this case, we are given the mass of hydrogen (H2) as 6 g. To calculate the number of moles, we can use the formula:

Number of moles = Mass of substance / Molar mass

The molar mass of hydrogen (H2) is approximately 2 g/mol. Therefore, the number of moles is:

Number of moles = 6 g / 2 g/mol

Now, we can calculate the volume of the gas using the ideal gas law equation. However, we need additional information about the pressure and temperature to obtain an accurate result. Please provide the pressure and temperature for a more precise calculation.

Task 5: Яка маса заліза відповідає кількості речовини металу 1,5 моль?

To calculate the mass of iron corresponding to a given amount of substance, we need to use the molar mass of iron (Fe). The molar mass of iron is approximately 55.845 g/mol.

The mass of iron can be calculated using the formula:

Mass = Number of moles x Molar mass

Given that the number of moles of iron is 1.5 mol, we can calculate the mass:

Mass = 1.5 mol x 55.845 g/mol

Calculating this, we find that the mass of iron corresponding to 1.5 mol of iron is approximately 83.768 g. [[3]]

Task 6: Відносна густина хлору за воднем – 35,5. Яка відносна молекулярна маса хлору?

The relative density of chlorine (Cl) with respect to hydrogen (H) is given as 35.5.

The relative density is defined as the ratio of the density of a substance to the density of a reference substance. In this case, the reference substance is hydrogen.

The relative molecular mass (also known as the relative molar mass or molecular weight) of a substance is the ratio of the average mass of one molecule of the substance to one-twelfth of the mass of an atom of carbon-12.

To calculate the relative molecular mass of chlorine, we can use the following formula:

Relative molecular mass = Relative density x Molar mass of reference substance

Given that the relative density of chlorine with respect to hydrogen is 35.5 and the molar mass of hydrogen is approximately 1 g/mol, we can calculate the relative molecular mass of chlorine:

Relative molecular mass of chlorine = 35.5 x 1 g/mol

Calculating this, we find that the relative molecular mass of chlorine is approximately 35.5 g/mol. [[4]]

Please note that the relative molecular mass of chlorine is different from its atomic mass, which is approximately 35.453 g/mol. The atomic mass takes into account the isotopic composition of chlorine, while the relative molecular mass is based on the relative density with respect to hydrogen.

I hope this helps! Let me know if you have any further questions.