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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: millerst on March 25, 2007, 12:07:32 PM

Title: Metal Activity Series
Post by: millerst on March 25, 2007, 12:07:32 PM

Hello,

I'm in a grade 11 Chemistry course and currently were covering single displacement reactions and the metal activity series.

I have the following question to do:
2.  Answer the following questions based the activity series you just created. The word observed means what changes did you see (such as color changes, solid formation, etc.) Write the equations (molecular and net ionic) for all reactions that occur.

a. What will be observed when a piece of Cu metal is added to a MgSO₄ solution?
b. What will be observed when a piece of Pb metal is added to a ZnSO₄ solution?
c. What will be observed when a piece of Fe metal is added to a AgNO₃ solution?
d. What will be observed when a piece of Ag metal is added to a Pb(NO₃)₂ solution?
e. What will be observed when a piece of Ca metal is added to a AgNO₃ solution?
 

Now, I'm not sure how to know what will be observed, But I've wrote the equations, and I'm not sure if those are right either. Here are my answers:

a) Cu + MgSO₄ --> CuSO₄ + Mg
b) Pb + ZnSO₄ --> PbSO + Zn
c) Fe + AgNO₃ --> FeNO + Ag
d) Ag + Pb(NO₃)₂ --> Ag(NO₃)₂ + Pb
e) Ca + AgNO₃ --> CaNO + Ag
**Should I always blanace my equations?

a) Copper Sulphate with magnesium on bottom.
b) Lead Sulphate with zinc on bottom.
c) Iron Nitrate with silver on bottom.
d) Silver Nitrate with with lead on bottom.
e) Calcium Nitrate with silver on bottom.


IF SOMEONE COULD HELP ME OUT/CORRECT MY MISTAKES I WOULD GREATLY LIKE THAT. THANKS TO ANYONE WHO CAN HELP.

Thanks,
Stefan

Title: Re: Metal Activity Series
Post by: Dan on March 25, 2007, 01:16:53 PM

You haven't used your activity series to answer the questions. What is the order of the ativity series for Cu, Mg, Pb, Zn, Fe, Ag and Ca?

Title: Re: Metal Activity Series
Post by: Yggdrasil on March 25, 2007, 01:50:52 PM

The activity series determines which metals will displace which metals in single replacement reactions.  Metals which are higher on the activity series (more reactive) will prefer to be in the ionic state whereas metals lower on the activity series (less reactive) will prefer to be in the elemental state.

For example, consider metal A and metal B.  Let's say that A is higher on the activity series than B.  Then, here will be the results for the following single replacement reactions:

A + BCl --> ACl + B
ACl + B --> no reaction

As for your answers, you should always balance your chemical equations.  For your observations, if a metal forms, you should note that, but certain ions have certain colors.  If a colored ion is formed in the reaction/removed in the reaction, then you can note the color change.

Title: Re: Metal Activity Series
Post by: millerst on March 26, 2007, 04:52:36 PM

Thanks for the replys.

The Activity Series of Metals is:

Calcium                    *Most Reactive
Magnesium
Zinc
Iron
Lead
Copper
Silver                       *Least Reactive

So the following would be? :

a) Cu + MgSO₄ --> CuSO₄ + Mg
b) 4Pb + ZnSO₄ --> 4PbSO + Zn
c) Fe + AgNO₃ --> No reaction
d) Ag + Pb(NO₃)₂ --> Ag(NO₃)₂ + Pb
e) 3Ca + AgNO₃ --> 3CaNO + Ag

I'm not sure but I think those are correct.

Also it's obvious which metals form, but how do you know about the colours?

Title: Re: Metal Activity Series
Post by: Borek on March 26, 2007, 05:17:34 PM

Quote from: millerst on March 26, 2007, 04:52:36 PM

The Activity Series of Metals is:

Calcium                    *Most Reactive
Magnesium
Copper
Silver                       *Least Reactive

So the following would be? :

a) Cu + MgSO₄ --> CuSO₄ + Mg

So you mean one of the most reactive metals will be displaced by one of the least reactive?

Title: Re: Metal Activity Series
Post by: millerst on March 26, 2007, 05:22:48 PM

Figures I'm doing to backwards  :(

a) Cu + MgSO₄ --> No Reaction
b) Pb + ZnSO₄ --> No Reaction
c) Fe + AgNO₃ --> FeNO₃ + Ag
d) Ag + Pb(NO₃)₂ --> No Reaction
e) 3Ca + AgNO₃ --> 3CaNO₃ + Ag

Does that look better then? That makes more sense anyways...

Title: Re: Metal Activity Series
Post by: Yggdrasil on March 26, 2007, 05:36:48 PM

The equations are right conceptually, but you have the formulas for iron nitrate and calcium nitrate wrong.

Title: Re: Metal Activity Series
Post by: millerst on March 26, 2007, 05:49:00 PM

Well because they are multi valent ions I'm not sure which charge get's assigned to Iron... Should it be iron (II) 2+, or Iron (III) 3+?

c) Fe + AgNO₃ --> FeNO₃ + Ag
e) 3Ca + AgNO₃ --> 3CaNO₃ + Ag

should be?
e) 18Ca + 6AgNO₃ --> 6Ca₃NO₂ + 6Ag

Title: Re: Metal Activity Series
Post by: Yggdrasil on March 26, 2007, 07:33:47 PM

I'm not exactly sure what oxidation state the iron would adopt either.  However for (e), calcium ions have a +2 charge and nitrate ions have a -1 charge.  Therefore the correct formula for calcium nitrate is Ca(NO₃)₂.

Title: Re: Metal Activity Series
Post by: millerst on March 26, 2007, 07:47:49 PM

Hey thanks, did a little research, it's Fe(NO3) for Iron(III) nitrate.

Title: Re: Metal Activity Series
Post by: Yggdrasil on March 26, 2007, 08:02:21 PM

Iron (III) nitrate is Fe(NO₃)₃.

Title: Re: Metal Activity Series
Post by: millerst on March 26, 2007, 08:08:48 PM

LOL, opps didn't copy it quite right... Fe(NO3)3

Thanks anyways