Yes its Chemical Energy released in the form of heat.
Answer:
The mole fractions:




Explanation:
The reaction described is:

The limiting reactant is the HBr (oxygen is in excess).
a) The mass (in moles) balance for this sistem:
(the 0.78 is because of the fractional conversion)

(the 1.25 is because of the oxygen excess)
There is only one degree of freedom in this sistem, you can either deffine the moles of HBr you have or the moles of Br2 you want to produce. The other variables are all linked by the equations above.
b) Base of calculation 100 mol of HBr:




The mole fractions:




Answer:
4
Explanation:
The weight will decrease.
Because the value of acceleration due to gravity is decreasing thus the weight of object will also decrease.
Intermolecular bonding:
Water is a polar molecule exhibit dispersion forces and hydrogen bonding
Salt is a polar molecule exhibit dispersion forces and dipole dipole bonding
Same bonding capacity therefore similar bonding capacity, therefore salt able to dissolves in water