How do I write the formula for the following compounds?
1.beryllium oxide
2. sodium sulfate
3.aluminum arsenide
I know how to write out the names but not the formula
BeO
Na2SO4
AlAs
To write the formula for a compound, you need to know the charges of the elements involved. Here's how you can determine the formulas for the compounds you mentioned:
1. Beryllium oxide:
Beryllium (Be) has a charge of +2, and oxygen (O) has a charge of -2. Since both charges need to balance out, you would need two Be atoms to balance out the two O atoms. Therefore, the formula for beryllium oxide is BeO.
2. Sodium sulfate:
Sodium (Na) has a charge of +1, and sulfate (SO4) has a charge of -2. To balance the charges, you would need two Na ions to match the overall -2 charge from sulfate. Therefore, the formula for sodium sulfate is Na2SO4.
3. Aluminum arsenide:
Aluminum (Al) has a charge of +3, and arsenic (As) has a charge of -3. You can see that both charges are already balanced, so there is no need for multiple atoms. Therefore, the formula for aluminum arsenide is AlAs.
Remember, when writing the formula for a compound, the overall charge must be neutral, meaning the positive (cation) and negative (anion) charges must balance each other out.