This group of elements is typically non-reactive because they have a full outer shell

group ia (alkali metals)
group viia (halogens)
group viiia (noble gases)
transition metals

Reaction rate depends on how many molecules are coming into contact with each other with enough energy to react. increasing the temperature of the reactants will increase -

Tin has ten stable isotopes. the heaviest, 124sn, makes up 5.80% of naturally occuring tin atoms. how many atoms of 124sn are present in 82.0 g of naturally occurring tin? what is the total mass of the 124sn atoms in this sample?

What three things determine the shape and size of a puddle when water is poured out onto a surface