In the chemical formula 2Ca(ClO2)2, how many atoms of oxygen are present?

• A. 2
• B. 4
• C. 8
• D. 12

Answer: (C)

Verified step by step guidance

1. Identify the chemical formula given: 2Ca(ClO2)2. This means there are 2 formula units of Ca(ClO2)2.
2. Focus on the subunit (ClO2)2. Inside the parentheses, ClO2 is a group, and the subscript 2 outside the parentheses means there are 2 ClO2 groups per formula unit.
3. Determine the number of oxygen atoms in one ClO2 group. Since the formula is ClO2, there are 2 oxygen atoms per ClO2 group.
4. Calculate the total oxygen atoms in one formula unit of Ca(ClO2)2 by multiplying the number of oxygen atoms in one ClO2 group by 2 (because of the subscript outside the parentheses): 2 oxygen atoms × 2 = 4 oxygen atoms per formula unit.
5. Since there are 2 formula units (indicated by the coefficient 2 in front), multiply the oxygen atoms per formula unit by 2: 4 oxygen atoms × 2 = 8 oxygen atoms in total.