Question

Вычислите массу оксида хрома(III), которую можно получить термическим разложением 3,7 г гидроксида хрома(III).

Answer 1

         3,7 г                        Х г
     2Cr(OH)3       ->       Cr2O3      +      3H2O
n=2 моль                       n=1 моль
М = 103 г/моль              М = 152 г/моль
m=206 г                          m=152 г

3,7 г Cr(OH)3    -    Х г Cr2O3
206 г Cr(OH)3  -    152 г Cr2O3
m(Cr2O3) = 3,7 * 152 / 206 =2,7 г

Answer 2

Дано
m(Cr(OH)3)=3.7g
----------------------
m(Cr2O3)-?
  3.7                   X
2Cr(OH)3-->Cr2O3+3H2O M(Cr(OH)3)=103 g/mol M(Cr2O3)=152 g/mol
  2*103             152
3.7 / 206 = X / 152
X=2.73 g
ответ 2.73 г

Answer 3

Calculation of the Mass of Chromium(III) Oxide

To calculate the mass of chromium(III) oxide (Cr2O3) that can be obtained from the thermal decomposition of 3.7 g of chromium(III) hydroxide (Cr(OH)3), we need to consider the molar ratios between the reactants and products.

The balanced chemical equation for the thermal decomposition of chromium(III) hydroxide is:

2Cr(OH)3(s) → Cr2O3(s) + 3H2O(g)

From the equation, we can see that 2 moles of chromium(III) hydroxide react to form 1 mole of chromium(III) oxide.

To calculate the mass of chromium(III) oxide, we need to convert the mass of chromium(III) hydroxide to moles using its molar mass, and then use the molar ratio to determine the mass of chromium(III) oxide.

Here are the steps to calculate the mass of chromium(III) oxide:

1. Calculate the molar mass of chromium(III) hydroxide (Cr(OH)3): - Chromium (Cr) has a molar mass of 51.9961 g/mol. - Oxygen (O) has a molar mass of 15.999 g/mol. - Hydrogen (H) has a molar mass of 1.00784 g/mol. - The molar mass of chromium(III) hydroxide is calculated as follows: Molar mass of Cr(OH)3 = (1 * Molar mass of Cr) + (3 * Molar mass of O) + (3 * Molar mass of H)

2. Convert the mass of chromium(III) hydroxide to moles: - Moles of Cr(OH)3 = Mass of Cr(OH)3 / Molar mass of Cr(OH)3

3. Use the molar ratio to calculate the moles of chromium(III) oxide: - Moles of Cr2O3 = (Moles of Cr(OH)3) / 2

4. Convert the moles of chromium(III) oxide to mass: - Mass of Cr2O3 = Moles of Cr2O3 * Molar mass of Cr2O3

Now, let's perform the calculations:

1. Molar mass of chromium(III) hydroxide (Cr(OH)3): - Molar mass of Cr = 51.9961 g/mol - Molar mass of O = 15.999 g/mol - Molar mass of H = 1.00784 g/mol - Molar mass of Cr(OH)3 = (1 * 51.9961) + (3 * 15.999) + (3 * 1.00784) g/mol

2. Moles of chromium(III) hydroxide (Cr(OH)3): - Moles of Cr(OH)3 = 3.7 g / (Molar mass of Cr(OH)3) mol

3. Moles of chromium(III) oxide (Cr2O3): - Moles of Cr2O3 = (Moles of Cr(OH)3) / 2 mol

4. Mass of chromium(III) oxide (Cr2O3): - Mass of Cr2O3 = (Moles of Cr2O3) * (Molar mass of Cr2O3) g

Please note that the molar mass of chromium(III) oxide (Cr2O3) is not provided in the search results. To complete the calculation, we need the molar mass of Cr2O3, which is 151.9904 g/mol.

Therefore, the mass of chromium(III) oxide (Cr2O3) that can be obtained from the thermal decomposition of 3.7 g of chromium(III) hydroxide (Cr(OH)3) is calculated as follows:

1. Calculate the molar mass of chromium(III) hydroxide (Cr(OH)3): - Molar mass of Cr(OH)3 = (1 * 51.9961) + (3 * 15.999) + (3 * 1.00784) g/mol

2. Convert the mass of chromium(III) hydroxide to moles: - Moles of Cr(OH)3 = 3.7 g / (Molar mass of Cr(OH)3) mol

3. Use the molar ratio to calculate the moles of chromium(III) oxide: - Moles of Cr2O3 = (Moles of Cr(OH)3) / 2 mol

4. Convert the moles of chromium(III) oxide to mass: - Mass of Cr2O3 = (Moles of Cr2O3) * (Molar mass of Cr2O3) g

Please note that the molar mass of chromium(III) oxide (Cr2O3) is not provided in the search results. To complete the calculation, we need the molar mass of Cr2O3, which is 151.9904 g/mol.

Please provide the molar mass of chromium(III) oxide (Cr2O3) to complete the calculation.