How many moles are in 250.0 grams of KBr?

1 answer

To calculate the number of moles in 250.0 grams of KBr (potassium bromide), you need to know the molar mass of KBr, which is the sum of the atomic masses of potassium (K) and bromine (Br).

The atomic masses are:
- Potassium (K) = 39.10 g/mol
- Bromine (Br) = 79.90 g/mol

So, the molar mass of KBr is:
39.10 g/mol (K) + 79.90 g/mol (Br) = 119.00 g/mol

Now use the formula: moles = mass / molar mass

moles = 250.0 g / 119.00 g/mol = 2.10 moles

Therefore, there are 2.10 moles in 250.0 grams of KBr.