a. Write the formula for copper (II) phosphate
b. Calculate the molecular weight for copper (II) phosphate
c. Calculate the number of moles of copper (II) phosphate in 129.4 g of copper (II) phosphate.
d. Calculate the total number of atoms of phosphorus in 129.4 g of copper (II) phosphate.
The Correct Answer and Explanation is :
a. Formula for Copper (II) Phosphate
The formula for copper (II) phosphate is Cu₃(PO₄)₂. This is based on copper’s +2 oxidation state (Cu²⁺) and phosphate’s -3 charge (PO₄³⁻). To balance the charges, you need 3 copper ions for every 2 phosphate ions, resulting in the formula Cu₃(PO₄)₂.
b. Molecular Weight of Copper (II) Phosphate
To calculate the molecular weight of copper (II) phosphate (Cu₃(PO₄)₂), we sum the atomic weights of each element in the formula:
- Atomic weight of Copper (Cu) = 63.55 g/mol
- Atomic weight of Phosphorus (P) = 30.97 g/mol
- Atomic weight of Oxygen (O) = 16.00 g/mol
The molecular weight is calculated as:
[
\text{Molar Mass} = 3 \times 63.55 \, \text{g/mol} + 2 \times (30.97 \, \text{g/mol} + 4 \times 16.00 \, \text{g/mol})
]
[
\text{Molar Mass} = 3 \times 63.55 + 2 \times (30.97 + 64.00)
]
[
\text{Molar Mass} = 190.65 + 2 \times 94.97
]
[
\text{Molar Mass} = 190.65 + 189.94 = 380.59 \, \text{g/mol}
]
Thus, the molecular weight of Cu₃(PO₄)₂ is 380.59 g/mol.
c. Number of Moles of Copper (II) Phosphate in 129.4 g
To calculate the number of moles of Cu₃(PO₄)₂ in 129.4 g, use the formula:
[
\text{Moles} = \frac{\text{Mass}}{\text{Molar Mass}}
]
[
\text{Moles} = \frac{129.4 \, \text{g}}{380.59 \, \text{g/mol}} = 0.340 \, \text{mol}
]
So, the number of moles of copper (II) phosphate in 129.4 g is 0.340 mol.
d. Total Number of Atoms of Phosphorus
To calculate the total number of atoms of phosphorus in 129.4 g of copper (II) phosphate:
- First, we find the number of moles of phosphorus atoms in 0.340 moles of Cu₃(PO₄)₂. Since each formula unit of Cu₃(PO₄)₂ contains 2 phosphorus atoms, the moles of phosphorus atoms will be:
[
\text{Moles of P} = 0.340 \, \text{mol} \times 2 = 0.680 \, \text{mol of P}
]
- Now, we use Avogadro’s number (6.022 × 10²³ atoms/mol) to find the total number of phosphorus atoms:
[
\text{Atoms of P} = 0.680 \, \text{mol of P} \times 6.022 \times 10^{23} \, \text{atoms/mol}
]
[
\text{Atoms of P} = 4.09 \times 10^{23} \, \text{atoms of P}
]
So, the total number of phosphorus atoms in 129.4 g of copper (II) phosphate is 4.09 × 10²³ atoms.
Explanation
- Formula of Copper (II) Phosphate (Cu₃(PO₄)₂): The compound copper (II) phosphate consists of copper ions in the +2 oxidation state (Cu²⁺) and phosphate ions (PO₄³⁻). To balance the charges, 3 copper ions pair with 2 phosphate ions, yielding Cu₃(PO₄)₂.
- Molecular Weight: The molecular weight is the sum of the atomic masses of all the elements in the compound. Copper, phosphorus, and oxygen contribute to the molecular weight of Cu₃(PO₄)₂, and the calculation yields 380.59 g/mol.
- Moles of Copper (II) Phosphate: The number of moles of Cu₃(PO₄)₂ in a given mass is calculated by dividing the mass by the molecular weight. For 129.4 g of Cu₃(PO₄)₂, the number of moles is 0.340 mol.
- Atoms of Phosphorus: Since each formula unit of Cu₃(PO₄)₂ contains 2 phosphorus atoms, the total number of moles of phosphorus atoms is double the moles of the compound. Then, multiplying by Avogadro’s number gives the total number of phosphorus atoms as 4.09 × 10²³.
I will now generate a visual representation of these calculations.
Here is a visual representation of the steps involved in calculating the copper (II) phosphate properties, including the formula, molecular weight, moles, and atoms of phosphorus. Each step is associated with the corresponding calculation or value derived.
