Group 2, or in the Alkaline Earth Metals section. This is due to the necessity to have a +2 charge to balance out or negate the -2 charge two Bromines carry.
It's pretty easy to balance equations! Basically you want to make sure that the number of each compound is equal on both sides of the arrow.
For example number one is
Fe + H2SO4 -> Fe2(SO4)3 + H2
A 3 in front of H2SO4 because there's a subscript of 3 on the right side.
Then a 3 in front of H2 because of the previous step.
Then add a 2 in front of Fe because of the 2 subscript in Fe2(SO4)3
Then add a 1 in front of Fe2(SO4)3 because you already have an equal number of each element.
<u>2</u>Fe + <u>3</u>H2SO4 -> <u>1</u>Fe2(SO4)3 + <u>3</u>H2
I hope this explanation helps! You should really do your homework because practice is everything when it comes to chemistry. You'll need to know how to do it for exams.
1 Hydrogen 1s1
2 Helium 1s2
3 Lithium 2s1
Anything that has mass and volume (takes up space) is called matter.
22.7 liters
The molar volume of an ideal gas depends on the temperature and pressure. One mole of any ideal gas occupies 22.7 liters at 0 0C and 1 bar (STP).
Hope this helped