Question

Определите количества вещества и число атомов кальция в 7г оксида кальция .​

Answer 1

Объяснение:

ВОТ ПОЖАЛУЙСТА ОТВЕТ УКАЗАН НА ФОТОГРАФИИ

Answer 2

Calculation of the Amount of Substance and Number of Atoms of Calcium in 7g of Calcium Oxide

To determine the amount of substance and the number of atoms of calcium in 7g of calcium oxide (CaO), we need to use the molar mass of calcium oxide and Avogadro's number.

The molar mass of calcium oxide (CaO) can be calculated by adding the atomic masses of calcium (Ca) and oxygen (O). According to the periodic table, the atomic mass of calcium is approximately 40.08 g/mol, and the atomic mass of oxygen is approximately 16.00 g/mol.

Therefore, the molar mass of calcium oxide (CaO) is: Molar mass of CaO = (1 * atomic mass of Ca) + (1 * atomic mass of O) Molar mass of CaO = (1 * 40.08 g/mol) + (1 * 16.00 g/mol) Molar mass of CaO = 56.08 g/mol

Now, we can calculate the amount of substance (in moles) of calcium oxide (CaO) in 7g using the formula: Amount of substance (moles) = Mass (g) / Molar mass (g/mol)

Amount of substance of CaO = 7g / 56.08 g/mol Amount of substance of CaO ≈ 0.125 mol

Since calcium oxide (CaO) has a 1:1 ratio of calcium (Ca) to oxygen (O) atoms, the number of atoms of calcium in 0.125 mol of calcium oxide is equal to the Avogadro's number multiplied by the amount of substance.

Number of atoms of calcium = Amount of substance (mol) * Avogadro's number Number of atoms of calcium = 0.125 mol * 6.022 x 10^23 atoms/mol

Therefore, the number of atoms of calcium in 7g of calcium oxide is approximately 7.53 x 10^22 atoms.

Please note that the calculations provided are approximate due to the rounded atomic masses used.