Question

Calculate the mass in grams of 8.0 mol of PbO.
Responses

1784 g
1784 g

1544 g
1544 g

1987 g
1987 g

223 g

Answer 1

To calculate the mass of 8.0 moles of lead(II) oxide (PbO), we first need to determine the molar mass of PbO.

- The atomic mass of lead (Pb) is approximately 207.2 g/mol.
- The atomic mass of oxygen (O) is approximately 16.0 g/mol.

Now, we can calculate the molar mass of PbO:

\[
\text{Molar mass of PbO} = \text{Mass of Pb} + \text{Mass of O}
\]

\[
\text{Molar mass of PbO} = 207.2\, \text{g/mol} + 16.0\, \text{g/mol} = 223.2\, \text{g/mol}
\]

Next, we can find the mass of 8.0 moles of PbO using the formula:

\[
\text{Mass} = \text{moles} \times \text{molar mass}
\]

\[
\text{Mass} = 8.0\, \text{mol} \times 223.2\, \text{g/mol} = 1785.6\, \text{g}
\]

Rounding to three significant figures, the mass of 8.0 moles of PbO is approximately **1786 g**.

However, that value wasn't listed in your options. The closest available answer is **1784 g**, which might be considered acceptable depending on significant figures.

So, the answer is:

**1784 g**.