<span>Take a look at this periodic table.
You start in the left upper corner (1s) then you go to the right untill you can't go further, then you go 1 row down and start at the left again.
So the order will be 1s,2s,2p,3s,3p,4s,3d,4p... etc</span>
Chemical equations are to be balanced to be able to follow the law of conservation of mass where it says that mass cannot be created or destroyed. Reactions should be that the mass of the reactants is equal to the mass of the products.
Maybe gas? because you can’t see it and it’s formed during a chemical reaction
