Which element is a gas?

A. Br
B. C
C. B
D. Be

A.Br

Explanation:

Bromine is the only gas from the choices provided. It belongs to the group of halogens, group 7.

It has atomic number of 35 and it belongs to the p-block on the periodic table.

C is carbon and carbon is a solid matter B is boron and boron is a metalloid Be is beryllium and silvery white metal

Only Bromine is the gas from the given choices. It is fuming liquid and when exposed, it becomes gaseous.

The independent variable is the type of music.the dependent variable is the pulse rate.the intervening variable is the age of the subject.if the mother does not like rock, her pulse is likely to not increase.the same might be true for the sister.the friend may like rap and gets excited.to establish cause/effect relationship, all of the subjects must be consistent.hope i .

Moles = mass/molar mass the molar mass of c20 = 12.011*20 = 240.22 g per mole therefore, the number of moles is 20 g / 240.22 g per mol = 0.0833 moles.