Why is ice melting a physical change? A. the atoms change into different atoms
B. Ice and water are different molecules
C. Ice and water are the same molecule

C

Explanation:

The atoms in the ice are just speeding up to turn into water, the molecules and atoms themselves don't change at all

1. 1 mole of anything contains 6.022x10^23 pieces  

d  

2. a  

3. c, number  

5. 1.24x10^24atoms / 6.022x10^23atoms/mole = 2moles h2 atoms  

6. fe2br3 mass = 2moles x mass fe + 3 moles x mass br  

molar mass = grams / number of moles = g/mole  

to find moles = g / molar mass  

to find mass = g = molar mass / moles