Chlorine has 2 stable isotopes, Cl-35 and Cl-37. If their exact masses are 34.9689 amu and 36.9695 amu, respectively, then what is the natural abundance of Cl-35? (The atomic mass of chlorine is 35.45 amu.)

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

1.43 x 10^-11 j the guy commented the awnser just making sure u see it .

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.