I'm not sure if what this question is asking but ill be assuming that the average molecular mass is required. An assuming that the abundance of each isotope is 50% the average molecular mass is 69.82 amu.
It begins by trying to solve a problem and or making a hypothesis.
Physical Properties<span>: </span>Physical properties<span> can be observed or measured without changing the composition of matter. </span>Physical properties<span> are used to observe and describe matter. so physical changes are the change in temperature of the land and the evaporation of water and change humidity of the air. chemical change is the ripening of the orange</span>
