A sample of CaCO3 has a mass of 751 grams. How many total atoms are present in this sample?

• A. 4.52 × 10^{24} atoms
• B. 7.51 × 10^{25} atoms
• C. 1.35 × 10^{25} atoms
• D. 2.26 × 10^{24} atoms

Answer: (C)

Verified step by step guidance

1. Determine the molar mass of calcium carbonate (CaCO\_3) by adding the atomic masses of its constituent atoms: calcium (Ca), carbon (C), and oxygen (O). The formula is: \(\text{Molar mass of CaCO\_3} = M_{Ca} + M_C + 3 \times M_O\).
2. Calculate the number of moles of CaCO\_3 in the 751 gram sample using the formula: \(\text{moles} = \frac{\text{mass}}{\text{molar mass}} = \frac{751}{\text{molar mass of CaCO\_3}}\).
3. Find the total number of formula units of CaCO\_3 by multiplying the moles by Avogadro's number (\$6.022 \times 10^{23}\( formula units per mole): \)\text{formula units} = \text{moles} \times 6.022 \times 10^{23}$.
4. Determine the total number of atoms in the sample by recognizing that each formula unit of CaCO\_3 contains 5 atoms (1 Ca + 1 C + 3 O). Multiply the total formula units by 5: \(\text{total atoms} = \text{formula units} \times 5\).
5. Combine all the steps to calculate the total number of atoms in the 751 gram sample of CaCO\_3.