Answer:
MgBr2
Explanation:
On the periodic table, Magnesium has 2+ charge and Bromine has -1 charge.
You cross charges and get MgBr2
What happens is that the sodium solution when put in water reacts and creates thermal energy .
Explanation:
When magnesium metal burns is heated i the air it forms magnesium oxide.The balanced chemical reaction is given as:

2 moles of magnesium metal when reacts with 1 moles of oxygen it gives 2 moles of magnesium oxide which is white in color.
Some times along with formation of magnesium oxide small amount of magnesium nitride also produced due to which magnesium oxide appears grey in color .The balanced chemical reaction is given as:

3 moles of magnesium combines with 1 mol of nitrogen gas to to give 1 mol of magnesium nitride.
Answer:
You should not use an open flame to heat the solvent and the solvent should be heat in a stoppered flask to vapour away from the open flame
Explanation: