Ted wants to hang a wall clock on the wall by using a string. if the mass of the wall clock is 0.250 kilograms, what should be the tension of the string so that it can sustain the weight of the wall clock?

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.