Question

2. Quantos mole s temos em 17 g de Ca(OH)2? (Ca = 40 u. O = 16 u e H = 1 u)​

Answer 1

Massa molar:

$M_{Ca(OH)_2} = 40 + (16 + 1) \cdot 2\\M_{Ca(OH)_2} = 40 + 17 \cdot 2\\M_{Ca(OH)_2} = 40 + 34\\M_{Ca(OH)_2} = 74g/mol$

Número de mols:

$n = \frac mM\\n = \frac{17}{74}\\\boxed{n \approx 0,23mol}$