Question

M(CaO)=5,6г m(H2O)=1,8г m(Ca(OH)2)-?

Answer 1

Ответ:7,4

Объяснение:CaO+H2O=Ca(OH)2

m(Ca(OH)2) - X

m(CaO) - Mr(Ca(OH)2), Mr(CaO) - m(Ca(OH)2)

5.6*74/X*56

X=5.6*74/56

X=7,4

Answer 2

To find the mass of calcium hydroxide (Ca(OH)2), we can use stoichiometry and the given masses of calcium oxide (CaO) and water (H2O).

First, we need to write the balanced chemical equation for the reaction between calcium oxide (CaO) and water (H2O) to form calcium hydroxide (Ca(OH)2):

CaO + H2O -> Ca(OH)2

Now, we can determine the molar masses of the compounds involved:

• CaO (calcium oxide): 40.08 g/mol (calcium) + 16.00 g/mol (oxygen) = 56.08 g/mol
• H2O (water): 2.02 g/mol (hydrogen) + 16.00 g/mol (oxygen) = 18.02 g/mol
• Ca(OH)2 (calcium hydroxide): 40.08 g/mol (calcium) + 2 * 16.00 g/mol (oxygen) + 2 * 1.01 g/mol (hydrogen) = 74.10 g/mol

Now, we can set up a proportion to find the mass of Ca(OH)2 formed:

(5.6 g CaO) / (56.08 g/mol CaO) = (x g Ca(OH)2) / (74.10 g/mol Ca(OH)2)

Cross-multiply and solve for x:

5.6 g CaO * (74.10 g/mol Ca(OH)2) / (56.08 g/mol CaO) ≈ 7.42 g Ca(OH)2

So, the mass of calcium hydroxide (Ca(OH)2) formed is approximately 7.42 grams.