Will mark !i don't understand this. if the density of an object is affected by its mass, then have the highest density and have the lowest density

If the density of an object is affected by its mass, then osmium will have the highest density and hydrogen will have the lowest density

Density = mass/volume or D = m/V

If we hold V constant, we can write D = km. where k = 1/V.

Thus, D ∝ m. As the mass of a fixed volume of a substance increases, the density increases.

The mass of H₂ in 1 cm³ 0.080 g. The mass of Os in 1 cm³ is 22.6 g.

However, there are substances with even higher densities. For example, the material at the centre of a neutron star is so dense that 1 cm³ of the material has a mass of 10¹² kg!

i'm pretty sure its b i might be wrong though!

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.