Question

(a) Orange bromine gas, Br$_{2}$, is put into the bottom of a gas jar which is immediately sealed.
After a short time, the bromine gas spreads out to fill the gas jar.
This process is called diffusion.
Fig. 11.1 shows the diffusion of bromine.

Describe the process of diffusion in terms of the movement of particles.
…………………………………………………………………………………………………………………………………
…………………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………………… 
(b) Chlorine and bromine are both halogens.
State the name of one other element that is a halogen.
………………………………………………………………………………………………………………………………… 
(c) Chlorine is in Period 3 of the Periodic Table.
Describe the change in metallic character across Period 3.
…………………………………………………………………………………………………………………………………
…………………………………………………………………………………………………………………………………
(d) Explain why the drinking water for a city is treated with chlorine.
…………………………………………………………………………………………………………………………………
……………………………………………………………………………………………………………………………

(e) Complete the dot-and-cross diagram to show the bonding in a molecule of chlorine Cl$_{2}$.

Only show the outer shell electrons.

(f) Hydrogen and chlorine combine to make hydrogen chloride, HCl.
(i) Balance the symbol equation for this reaction.
                     H$_{2}$ + Cl$_{2}$→  …….. HCl 
(ii) Explain why hydrogen chloride is a covalent compound and not an ionic compound.
………………………………………………………………………………………………………………………….
…………………………………………………………………………………………………………………….