Final answer:
The molecular mass of cobalt(II) dihydrogen phosphate is calculated by determining the formula of the compound and summing the atomic masses of cobalt, hydrogen, phosphorus, and oxygen, resulting in a molecular mass of 252.91 amu.
Step-by-step explanation:
To calculate the molecular (formula) mass of cobalt(II) dihydrogen phosphate, we'll need to determine the formula of the compound and then add the atomic masses of each element in the formula. Cobalt(II) indicates that cobalt has a 2+ charge, and dihydrogen phosphate is [(H₂PO₄)]⁻, which has a 1- charge. Therefore, the formula is Co(H₂PO₄)₂ to balance the charges. Using standard atomic masses, we calculate the molecular mass as follows:
- Cobalt (Co): 58.93 amu
- Hydrogen (H): 1.01 amu × 4 = 4.04 amu
- Phosphorus (P): 30.97 amu × 2 = 61.94 amu
- Oxygen (O): 16.00 amu × 8 = 128.00 amu
Then we add these together:
58.93 (Co) + 4.04 (H) + 61.94 (P) + 128.00 (O) = 252.91 amu.
Therefore, the molecular mass of cobalt(II) dihydrogen phosphate is 252.91 amu when rounded to the hundredths place.