Question

СРОЧНО ПОМОГИТЕ Визнач масові частки елементів (%) у сполуці Cr2(SiO3)3, і обери їх значення із запропонованих варіантів відповідьмасова частка Хрому:25,343,431,3масова частка Силіцію:25.343.431.3масова частка Оксигену:25, 343, 431, 3​

Answer 1

масова частка Хрому: 31,3%

масова частка Силіцію: 25.3%

масова частка Оксигену: 43, 4%

Answer 2

Determining the Mass Percentages of Elements in Cr2(SiO3)3

To determine the mass percentages of elements in the compound Cr2(SiO3)3, we can start by calculating the molar mass of the compound and then use it to find the mass percentages of each element.

The molar mass of Cr2(SiO3)3 can be calculated by adding the molar masses of chromium (Cr), silicon (Si), and oxygen (O) in the compound.

The molar masses of the elements are as follows: - Chromium (Cr): 51.996 g/mol - Silicon (Si): 28.0855 g/mol - Oxygen (O): 15.999 g/mol

The molar mass of Cr2(SiO3)3 can be calculated as follows: Molar mass = (2 * molar mass of Cr) + (1 * molar mass of Si) + (9 * molar mass of O)

Let's calculate the molar mass of Cr2(SiO3)3:

Molar mass = (2 * 51.996 g/mol) + (28.0855 g/mol) + (9 * 15.999 g/mol) Molar mass = 103.992 g/mol + 28.0855 g/mol + 143.991 g/mol Molar mass = 275.0685 g/mol

Now that we have the molar mass of Cr2(SiO3)3, we can proceed to calculate the mass percentages of each element in the compound.

Mass Percentages of Elements in Cr2(SiO3)3

1. Mass Percentage of Chromium (Cr): To calculate the mass percentage of chromium in Cr2(SiO3)3, we can use the following formula: Mass percentage of chromium = (Number of moles of chromium * Molar mass of chromium) / Molar mass of Cr2(SiO3)3

The number of moles of chromium in Cr2(SiO3)3 is 2 moles, as indicated by the chemical formula.

Mass percentage of chromium = (2 * 51.996 g/mol) / 275.0685 g/mol Mass percentage of chromium = 103.992 g/mol / 275.0685 g/mol Mass percentage of chromium ≈ 37.81%

Therefore, the mass percentage of chromium in Cr2(SiO3)3 is approximately 37.81%.

2. Mass Percentage of Silicon (Si): To calculate the mass percentage of silicon in Cr2(SiO3)3, we can use the following formula: Mass percentage of silicon = (Number of moles of silicon * Molar mass of silicon) / Molar mass of Cr2(SiO3)3

The number of moles of silicon in Cr2(SiO3)3 is 1 mole, as indicated by the chemical formula.

Mass percentage of silicon = (1 * 28.0855 g/mol) / 275.0685 g/mol Mass percentage of silicon = 28.0855 g/mol / 275.0685 g/mol Mass percentage of silicon ≈ 10.22%

Therefore, the mass percentage of silicon in Cr2(SiO3)3 is approximately 10.22%.

3. Mass Percentage of Oxygen (O): To calculate the mass percentage of oxygen in Cr2(SiO3)3, we can use the following formula: Mass percentage of oxygen = (Number of moles of oxygen * Molar mass of oxygen) / Molar mass of Cr2(SiO3)3

The number of moles of oxygen in Cr2(SiO3)3 is 9 moles, as indicated by the chemical formula.

Mass percentage of oxygen = (9 * 15.999 g/mol) / 275.0685 g/mol Mass percentage of oxygen = 143.991 g/mol / 275.0685 g/mol Mass percentage of oxygen ≈ 52.17%

Therefore, the mass percentage of oxygen in Cr2(SiO3)3 is approximately 52.17%.

In summary: - Mass percentage of Chromium (Cr): Approximately 37.81% - Mass percentage of Silicon (Si): Approximately 10.22% - Mass percentage of Oxygen (O): Approximately 52.17%