Calculate the molar mass of HgO. Round your answer to one decimal place.
The Correct Answer and Explanation is:
To calculate the molar mass of HgO (mercury(II) oxide), we need to sum the atomic masses of mercury (Hg) and oxygen (O) based on their values from the periodic table:
- Mercury (Hg): 200.6 g/mol
- Oxygen (O): 16.0 g/mol
Molar Mass of HgO:
$$
\text{Molar mass of HgO} = \text{Atomic mass of Hg} + \text{Atomic mass of O}
$$
$$
\text{Molar mass of HgO} = 200.6 + 16.0 = \boxed{216.6 \text{ g/mol}}
$$
✅ Final Answer: 216.6 g/mol
🧪 Explanation (Approximately 300 Words):
The molar mass of a compound is the mass of one mole of that compound, measured in grams per mole (g/mol). To find it, we add together the atomic masses of all atoms present in one molecule (or formula unit) of the substance.
In this case, HgO is a binary compound composed of one atom of mercury (Hg) and one atom of oxygen (O).
- Mercury (Hg) is a heavy metal element with an atomic mass of 200.6 g/mol. It has a relatively high atomic mass because it has a large number of protons and neutrons.
- Oxygen (O) is a non-metal element and one of the most common elements in the Earth’s crust. It has an atomic mass of 16.0 g/mol.
Since the chemical formula of mercury(II) oxide is HgO, the compound contains:
- 1 atom of mercury
- 1 atom of oxygen
When calculating the molar mass:
- Multiply the number of atoms of each element by its atomic mass.
- Then add the results to find the total molar mass.
$$
\text{Hg: } 1 \times 200.6 = 200.6 \text{ g/mol} \
\text{O: } 1 \times 16.0 = 16.0 \text{ g/mol} \
\text{Total: } 200.6 + 16.0 = 216.6 \text{ g/mol}
$$
Thus, the molar mass of HgO is 216.6 g/mol, which is the mass of one mole of HgO molecules. This value is useful in stoichiometry, allowing chemists to relate grams of a substance to moles for chemical reactions.