Calculate the mass percent of a nacl solution in which 140g of nacl is dissolved in 4.50l of water at 25c (density = 0.997g/ml).

your parents i think this could be it

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.