Ocr f321 23 may 2013~official discussion thread

oooooo revision

Wanna join in?

Guys I really want an a in this was 3 marks off a b and made them up in my coursework.. Havent started revising yet. Any tips on how to prepare during the next 24hours? Xxx I really need an A! (A)


Posted from TSR Mobile

yes please

I know its soluble in non polar solvents such as hexane, but I'm not too sure about the second part :-/

Okay then, explain trend in reactivity as you travel down group 2, make sure you go into detail as that would normally be worth 3-4 marks


Posted from TSR Mobile

Second part is right, double checked in book

As you go down group 2 the reactivity decreases. This i because there are more shells, so electron shielding will have no effect. This will also mean that nuclear attraction will also decrease down the group. Moreover, it is much easier to remove an electron from the outer shell.

I think I covered it

As you go down group 2 the reactivity decreases. This i because there are more shells, so electron shielding will have no effect. This will also mean that nuclear attraction will also decrease down the group. Moreover, it is much easier to remove an electron from the outer shell.

I think I covered it

You might of got mixed up with Group 7

I got :
Gets more reactive as you go down.
Increased AtomicRadius
IncreasedShielding
Decreasing NuclearAttraction
Although there's increasing nuclear charge the increasing shielding and radius outweighs this.
Easier to remove electron from outer shell. TyTy
Posted from TSR Mobile

As you go down group 2 the reactivity decreases. This i because there are more shells, so electron shielding will have no effect. This will also mean that nuclear attraction will also decrease down the group. Moreover, it is much easier to remove an electron from the outer shell.

I think I covered it

Okay, you might have got confused a little. I'll give you a hint and see if you can change and improve your answer. Group 2 are metals which want to lose electrons.

Have another try

Not quite. Reactivity actually increases down group 2. You're right that there are more shells but this means that there is more electron shielding down the group as there are more inner-shell electorns to repel the outer-shell electrons. Also, the increase in shells means that the atomic radius increases. Both reduce the electrostatic attraction between the nucleus and the outer-shell electrons making it easier for the group 2 elements to lose their outer two electrons down the group (this is what they aim to do to achieve a full otuer shell fo electorns/elec. config. of a noble gas).
Nuclear charge does increase down the group but it's outweighed by the increase in atomic radius and electron shielding. Hope that clarifies it -sorry it was a bit of a rant

What is the exact definition of a Dative Bond?

Okay,

As you go down group 2 the reactivity increases. This is because the atomic radii increases, so they will be more shielding. This will also mean that the nuclear attraction decreases too. This will mean that it will be easier to lose an outer electron.

Yeah, that all seems correct but there isn't any increase in nuclear charge as they are all in the same group, so all have the same charge

Yeah that sounds a lot better Ask me a question now?

Actually the nuclear charge does increase down the group as the elements' atoms have more protons in their nuclei.