Answer:
50
Explanation:
If you want a percent as a decimal so you can divide you must make it a decimal for example in your case it would be like this, 0.05, then all you do is divide 1,000 by 0.05
I think it's RbCl and CaO
The d sublevel has 5 orbitals, so can contain 10 electrons max
X/24=0.2moles
x=4.8gram of magnesium is needed to have 0.2 moles of Mg