Answer:
The heat energy stored within them changes
Explanation:
Heat energy is a function of the mass of a body, its specific heat capacity, and its temperature.
In this case, the bodies have the same specific heat capacity since they are made from the same material and the same temperature.
To get the quantity of heat stored in a body, we need to multiply all three parameters as shown below

An increase in mass, through an increase in the amount of substance of a material present, will cause a corresponding increase in the heat energy stored within the material
A homogeneous mixture has the same uniform appearance and composition throughout. Many homogeneous mixtures are commonly referred to as solutions. A heterogeneous mixture consists of visibly different substances.
A composition reaction produces a single substance from multiple reactants. A decomposition reaction produces multiple products from a single reactant. Combustion reactions are the combination of some compound with oxygen to make oxides of the other elements as products (although nitrogen atoms react to make N2).
Halogens (atoms with 7 valence electrons) and Hydrogen
or generally, atoms with their shells almost full