Final answer:
To convert 125.4 grams of MgSO4 to moles, you need to use the molar mass of MgSO4. The molar mass of MgSO4 is 120.3 g/mol. Therefore, 125.4 grams of MgSO4 is equal to 1.04 moles.
Step-by-step explanation:
To convert 125.4 grams of MgSO4 to moles, we need to use the molar mass of MgSO4.
The molar mass of MgSO4 is calculated by adding up the atomic masses of magnesium (Mg), sulfur (S), and oxygen (O) in one mole of MgSO4.
The atomic mass of Mg is 24.3 g/mol, the atomic mass of S is 32.1 g/mol, and the atomic mass of O is 16.0 g/mol.
Adding these up gives a molar mass of 120.3 g/mol for MgSO4.
Now we can use the formula:
Moles = Mass / Molar Mass
Plugging in the values, we have:
Moles = 125.4 g / 120.3 g/mol
= 1.04 moles
So, 125.4 grams of MgSO4 is equal to 1.04 moles.