Activity Order of Metals

[Vigo]

How are metals put in their order on the order of metal activiyt? From what I can infer, it is how violently they react in a substance but I am not sure.

[RyanJ]

How are metals put in their order on the order of metal activiyt? From what I can infer, it is how violently they react in a substance but I am not sure.

 

Yes thats basically it. Its more correctly called the Activity Series, metals are listed in order of decreasing ease of oxidation and increased east of reduction

 

http://en.wikipedia.org/wiki/Reactivity_series

 

Cheers,

 

Ryan Jones

[MulderMan]

Q: So the GCSE Science "Reactivity Series" is totally different to the real one?

 

thanks.

[RyanJ]

Q: So the GCSE Science "Reactivity Series" is totally different to the real one?

 

thanks.

 

Not really, they are pretty much the same

 

Maybe the "real one" has more metals in it but thats about the onlly differene as far as I am aware, the actual table its self remains the same

 

Cheers,

 

Ryan Jones

[MulderMan]

This is the data sheet from my exam board.

 

 

If I ommit the ones not used in the exam board one from the wikipedia table, the wikipedia table starts like this.

 

Potassium

Calcium

Sodium

 

The exam board one starts like this.

 

Potassium

Sodium

Calcium

 

Im just abit unsure which one is right?

 

Thanks.

[RyanJ]

Ah, I understand the question now.

 

Reactivity increases as you go down groups I and II... Seeing as Group I are more reactive then Group II anyway and Sodium being further up the table then Calcium I guess its open to debate, I personally agree with the Wikipedia one. Having seen Sodium and Calcium react I'd definatly say Sodium is more reactive.

 

Lets see what the chemistry experts have too say - maybe they may be able to say for shure which is more reactive

 

Cheers,

 

Ryan Jones

[YT2095]

the Electro-chemical or sometimes called the Electro-motive series is a better measurement than how violently something reacts, OR is position on the periodic table.

 

edit: seeing that table there, reminds me of how we used to remember it: People Sometimes Catch Malladies At Zoos, In The Lions Cage Someone Got Plenty.

another little bit of half usefull info for you

[woelen]

Reactivity is not only a function of electropositivity (or the position in the electrochemical series).

Reactivity also depends on things like solubility. A metal like Al is VERY reactive, but still it is stable, because the oxide layer protects the underlying metal.

 

Calcium also is very reactive, but Ca(OH)2 is only sparingly soluble and this makes the reaction between calcium and water somewhat sluggish. It makes the reaction between the water and calcium metal more difficult, because it blocks free access of water to the metal. If NaOH were slightly soluble in water, then Na would not react violently with water. It is the combination of electropositive nature and the perfect solubility of the reaction product, which makes Na (and K and heavier alkali metals) so reactive.

 

The effect of protective layer formation due to insoluble or sparingly soluble reaction products is nicely demonstrated with aluminium, when it is scratched and a small amount of mercury is put on the scratched area. The mercury forms an amalgam and this prevents the formation of an adhesive oxide layer. The Al is oxidized, but the oxide does not stick to the metal and hence the metal is corroded quickly. You can actually see it 'rot away', especially when it is humid.

[YT2095]

is nicely demonstrated with aluminium, when it is scratched and a small amount of mercury is put on the scratched area. The mercury forms an amalgam and this prevents the formation of an adhesive oxide layer. The Al is oxidized, but the oxide does not stick to the metal and hence the metal is corroded quickly. You can actually see it 'rot away'.

 

yeah, that SOoooo reminds me of adding freshly torn alu foil to gallium metal (and much less toxic than mercury) the reaction is fascinating to watch when you consider that it occurs at Room Temp, it`s like something you see in metal foundry at a 1000+c happening on your desk

 

and yes, before anyone says anything, the Simple Things still amuse/fascinate me (hope they always do!).

[jdurg]

Ah' date=' I understand the question now.

 

Reactivity increases as you go down groups I and II... Seeing as Group I are more reactive then Group II anyway and Sodium being further up the table then Calcium I guess its open to debate, I personally agree with the Wikipedia one. Having seen Sodium and Calcium react I'd definatly say Sodium is more reactive.

 

Lets see what the chemistry experts have too say - maybe they may be able to say for shure which is more reactive

 

Cheers,

 

Ryan Jones[/quote']

 

Heh. In that case it was very astute of them to completely leave lithium off of that list as it would be higher up than potassium is.

[RyanJ]

Heh. In that case it was very astute of them to completely leave lithium off of that list as it would be higher up than potassium is.

 

Really :S

 

So, can any of the experts resolve the issue, is Calcium mmore reactive than Sodium or vice versa?

 

Cheers,

 

Ryan Jones

[sunspot]

Another way to look at reactivity is via electronegativity. This indicates the affinity for electrons, with the lowest numbers being the most reactive with respect to losing electrons, the highest being the most reactive with respect to gaining electrons.