What is the smallest part of an element that has all the properties of that element?

If you burn 10 kilograms of wood in a fire (combustion) what is the weight of the products after the fire has finished burning the wood?

Consider the reaction: n2(g) + o2(g) ⇄ 2no(g) kc = 0.10 at 2000oc starting with initial concentrations of 0.040 mol/l of n2 and 0.040 mol/l of o2, calculate the equilibrium concentration of no in mol/l how would this be done?

What must be in balance for temperatures to remain constant?