When storm clouds produce lighting and thunder, what kind of energy is produced?

When many atoms are split in a chain reaction, a large explosion occurs. this is an example of what type of energy conservation

In a given chemical reaction, the energy of the products is greater than the energy of the reactants. which statement is true for this reaction?

Calculate the mass of an object that has a momentum of 100kg x m/sec and velocity of 4 m/sec