Answered

Carl makes the table below to determine the number of atoms of each element in the chemical formula [tex]\(4 \text{Ca} \left( \text{ClO}_3 \right)_2\)[/tex].

\begin{tabular}{|l|c|c|}
\hline
Element & Calculation & Total atoms \\
\hline
Calcium & [tex]\(1 \times 4\)[/tex] & 4 \\
\hline
Chlorine & [tex]\(1 \times 2\)[/tex] & 2 \\
\hline
Oxygen & [tex]\(3 \times 2\)[/tex] & 6 \\
\hline
\end{tabular}

What mistake did Carl make?

A. He did not multiply the calcium atoms by the subscript 2.

B. He did not add the coefficient 4 to the chlorine and oxygen atoms.

C. He did not add the subscript 2 to the calcium atoms.

D. He did not multiply the chlorine and oxygen atoms by the coefficient 4.



Answer :

GinnyAnswer
Let's analyze Carl's calculations for the chemical formula [tex]\( \text{4 Ca (ClO}_3\text{)}_2 \)[/tex]:

1. For Calcium:
- The coefficient in front of the formula is 4.
- There is 1 calcium (Ca) atom per formula unit.
- Therefore, the total number of calcium atoms = [tex]\( 1 \times 4 = 4 \)[/tex].
- Carl's calculation for calcium is correct.

2. For Chlorine:
- The subscript outside the parentheses indicates there are 2 chlorate (ClO[tex]\(_3\)[/tex]) units per formula unit.
- Each chlorate unit contains 1 chlorine (Cl) atom.
- Therefore, in each formula unit, there are [tex]\( 1 \times 2 = 2 \)[/tex] chlorine atoms.
- Considering the coefficient 4, the total number of chlorine atoms = [tex]\( 2 \times 4 = 8 \)[/tex].
- Carl's calculation for chlorine did not account for the coefficient 4, resulting in an incorrect total.

3. For Oxygen:
- Each chlorate unit (ClO[tex]\(_3\)[/tex]) contains 3 oxygen (O) atoms.
- With 2 chlorate units per formula unit, the total number of oxygen atoms per formula unit = [tex]\( 3 \times 2 = 6 \)[/tex].
- Considering the coefficient 4, the total number of oxygen atoms = [tex]\( 6 \times 4 = 24 \)[/tex].
- Carl's calculation for oxygen also did not account for the coefficient 4, resulting in an incorrect total.

Thus, Carl's mistake was that he did not multiply the chlorine and oxygen atoms by the coefficient 4.