Pls solve my problem quickly as i am junior, i am not expert in solving these: SiO2 + Na2CO3=Na2SiO3 +CO2 So how do CO2 get separated from products,and where did the 1 oxygen atom go, Is this equation needed to be balanced. Why is helium placed in the group of noble gases? Do it reacts? Why is hydrogen a non metal, if it is placed in 1a group? Do displacement reactions only take place between a metal and a non metal and do it only displaces non metal? How could be argon a non metal if it is a noble gas?