To know the density you also need to know the volume of the rock.
Answer:
A mixture of salt and sugar can be separated by the process of filtration.
a) the kinetic energy decreases as in a gas, the particles are widespread and move freely but in a liquid, their movement is more limited
Activation of energy is the foundation of chemical being react in a solution. If activation energy is not reached then no reaction would happen.
Cobalt because it has an atomic mass of 58 and 33 neutrons.