1. How many atoms are in 0.25 moles of carbon?

2. How many atoms are in 12.3 grams of sodium?

3. How many grams are there in 0.52 moles of boron?

4. How many grams are there in 2.0 moles of HCl?

5. How many moles are in 3.4 grams of HBr?

6. How many grams are there in 4.5x10^10 atoms of NaCl?

7. How many atoms are there in 45.1 grams of MgO?