Chemical energy is converted to thermal energy.
Answer: The possible molecular formula will be 
Explanation:
Mass of C= 27.3 g
Mass of O = 72.7 g
Step 1 : convert given masses into moles.
Moles of C =
Moles of O =
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For C =
For O =
The ratio of C : O = 1: 2
Hence the empirical formula is
The possible molecular formula will be=
The equation for the nuclear fusion reaction is,
4 ¹₁H → ₂⁴He + 2 ₁⁰e
Calculation of mass defect,
Δm = [mass of products - mass of reactants]
= 4(1.00782) - [4.00260 + 2(0.00054858)]
= 0.0275828 g/mole
Given that,
Mass of Hydrogen-1 = 2.58 g
The no. of moles of ₁¹H = 2.58 g / 1.00782 = 2.56 moles
Therefore, the mass defect for 2.58 g of ₁¹H is,
= 2.56 moles * (0.0275828 g / 4) = 0.01765 x 10⁻³ kg
Energy for (0.01765 x 10⁻³ kg) is,
= (0.01765 x 10⁻³ kg) (3.0 x 10⁸)² = 1.59 x 10¹² J
A - its condensation and gas particles have a higher kinetic energy