Question

Explain how to determine the total number of atoms in a chemical formula.​

Answer 1

To determine the total number of atoms in a chemical formula, follow these steps:

1. **Identify the elements in the formula:** A chemical formula consists of symbols representing the chemical elements present in the compound. For example, in the formula \( \text{H}_2\text{O} \), there are two elements: hydrogen (H) and oxygen (O).

2. **Look for subscripts:** Next to each element symbol, there may be a subscript, which indicates the number of atoms of that element in the compound. If there is no subscript next to an element, it is understood to be 1. For example:
- In \( \text{C}_6\text{H}_{12}\text{O}_6 \) (glucose), there are:
- 6 carbon (C) atoms
- 12 hydrogen (H) atoms
- 6 oxygen (O) atoms

3. **Add up the total atoms:** To find the total number of atoms, simply sum the number of atoms for each element:
- For \( \text{C}_6\text{H}_{12}\text{O}_6 \):
- 6 (C) + 12 (H) + 6 (O) = 24 total atoms.

4. **Consider parentheses and coefficients (if applicable):** If the formula includes parentheses and a coefficient outside, you need to distribute the coefficient to the subscripts within the parentheses. For example, in \( \text{2}(\text{C}_3\text{H}_4) \):
- First, recognize that \( \text{C}_3\text{H}_4 \) contains:
- 3 carbon (C) atoms and
- 4 hydrogen (H) atoms.
- Applying the coefficient (2):
- Carbon: \( 3 \times 2 = 6 \)
- Hydrogen: \( 4 \times 2 = 8 \)
- Then, add them together: \( 6 + 8 = 14 \) total atoms.

By following these steps, you can accurately calculate the total number of atoms in any chemical formula.