Question

question 4. the molar mass of zn(clo₄)₂ is ______.
164.84 g/mol.
260.55 g/mol.
264.29 g/mol.
267.45 g/mol.

Explanation:

Step1: List atomic masses

Atomic mass of Zn = $65.38\ \text{g/mol}$, Cl = $35.45\ \text{g/mol}$, O = $16.00\ \text{g/mol}$

Step2: Count each atom's quantity

1 Zn, 2 Cl, $2\times4=8$ O atoms

Step3: Calculate total mass

$$65.38 + (2\times35.45) + (8\times16.00)$$
$$=65.38 + 70.90 + 128.00$$
$$=264.28\ \text{g/mol}$$
(Minor discrepancy from rounding)

Answer:

264.29 g/mol.