Question

кальцій оксид масою 36,8 повністю розчинили у воді. Обчисліть масу та кількість речовини утвореного продукту.​

Answer 1

CaO + H2O = Ca(OH)2

m(CaO) = 36,8 г

m(Ca(OH)2) - ?

Решение:

1) μ(Ca(OH)2) = μ(СaO) = 36,8 г / 56 г/моль = 0,657 моль

2) m(Ca(OH)2) = 0,657 моль * 74 г/моль = 48,618 г

Ответ: 48,618 г

Answer 2

Calculation of Mass and Amount of Substance of the Product

To calculate the mass and amount of substance of the product formed when 36.8 grams of calcium oxide (CaO) is completely dissolved in water, we can use the chemical equation for the reaction between calcium oxide and water.

The balanced chemical equation for the reaction is: CaO + H2O → Ca(OH)2

From the balanced chemical equation, we can see that 1 mole of calcium oxide reacts with 1 mole of water to produce 1 mole of calcium hydroxide.

First, let's calculate the amount of calcium oxide in moles: The molar mass of calcium oxide (CaO) is 40.08 g/mol. So, the number of moles of calcium oxide is calculated as: 36.8 g / 40.08 g/mol = 0.919 moles [[1]].

Since the reaction is 1:1 between calcium oxide and water, the number of moles of calcium hydroxide formed will also be 0.919 moles.

Now, let's calculate the mass of calcium hydroxide formed: The molar mass of calcium hydroxide (Ca(OH)2) is 74.093 g/mol. So, the mass of calcium hydroxide formed is: 0.919 moles * 74.093 g/mol = 68.07 grams [[2]].

Therefore, when 36.8 grams of calcium oxide is completely dissolved in water, 68.07 grams of calcium hydroxide is formed, and the amount of substance of the product is 0.919 moles.