What is the mass of 1.9 moles of beryllium bromide (BeBr_)

168.820182 gram using the molecular weight calculator and the molar mass of BeBr2.

Explanation:

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.