A 25.0 L sample of gas contains 0.75 moles of bromine. At the same temperature and pressure, how many moles of gas would there be in a 10.5 L sample? What is the mass of the gas?

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8

b) nuclear ive learned that in a pedtrodic table