My teacher gave me the answers to this chemistry equation, but I don't understand. Can anyone help?

Question

The directions say predict the product of the following reactions.

The equation is:
Mg(OH)2 + AgCl

The answer he gave me for the products is:
Mg + OH + AgCl

I don't understand why the answer is not MgCl2 + AgCl.
Please help!!!

Answer 1

It is not a double replacement reaction since Mg(OH)2 is a very weak base and AgCl is a very weak salt

Answer 2

The reason, as best I can tell, is that you are studying dissociation and working your way up to net ionic equations... You teacher is trying to get you to use the solubility rules/solubility charts (look in the index of you book for that and you should find it -- it will either be a set of about 6 rules with things like "all chlorides are soluble except...." or a chart that you find the anion on one side and the cation on the other and then follow to where they meet to determine solubility).

I first answered this without looking at the chart and assumed that Mg(OH)2 was soluble based on the way your teacher wrote it... On the charts I found, it isn't soluble. So there is an error there. Assuming your teacher made a mistake reading the solubility table, and going with the idea that when they read it they saw Mg(OH)2 as soluble the following information would clarify:


Mg(OH)2 breaks apart (dissociates) into Mg+2 and 2 OH- because it is soluble in water (this is where the error in your teacher's answer is, but the rest will assume that Mg(OH)2 is soluble).

AgCl stays as AgCl because it is insoluble in water

The answer your teacher gave is telling what you would see if you looked into a glass of water that someone had put Mg(OH)2 and AgCl into -- there would be AgCl sitting at the bottom because it's insoluble, and Mg+2 and OH- ions dissolved in the water...

To make this clearer it would better be written like this:

Mg+2 (aq) + 2 OH-(aq) + AgCl (s)

(aq) = aqueous, dissolved in water, soluble
(s) = solid, unable to dissolve in water, insoluble

Hope that helps

Answer 3

If we assume this reaction is taking place in water, you need to look at the solubilities of the reactants and any potential products. AgCl is insoluble, Mg(OH)2 is sparingly soluble. The possible products are MgCl2 which is soluble and AgOH (AgOH would actually decompose into Ag2O, but that is beside the point here). Your teacher is saying that the insoluble AgCl would remain unchanged and that the Mg(OH)2 would dissolve to give Mg2+ and 2OH-. I would say that the majority of Mg(OH)2 would not dissolve, so you get essentially no reaction whatsoever.

If MgCl2 were formed as you want to happen, it would immediately dissolve into Mg2+ and 2Cl-.

Answer 4

I should get a new chemistry teacher if I were you.

There is no reaction between pretty insoluble Mg(OH)2 and pretty insoluble AgCl. The first is a weak base, and the second a salt.

Answer 5

inform you a clean ABC approach..it rather works each the place and it rather is somewhat common. believe me .. you have the equation actual? ok + O2 ------> K2O call each species from A to what ever you have.. A B C ok + O2 ------> K2O once you provide the respected ABC to each and each species, you presently count quantity how many ingredient you have in each and each team (ABC). you purely could variety of factors, ok and O and you will variety an equation from all the winning factors. ok-- you have a million ok on the reactant(team A) and 2 ok on the producat element(groupC) O--- you have 2 on the reactant (team B)and a million on the product(team C) so which you equalize the variety of electrons on the reactant and product element... So ok= 1A = 2C O = 2B = C Now you sometimes start up by letting A to be a million.. So if A = a million and A=2C a million=2C c=a million/2 and 2B=C (from this 2nd reaction from O) 2B = a million/2 B=a million/4 So now to procure A=a million B=a million/4 c=a million/2 yet we don't desire to have fractions with the intention to multiply the numbers to have an entire quantity. keep in mind you ahve to multiply all 3 numbers with an identical quantity and make all of them entire numbers. for this reason we could use 4 coz that's going to loose B and additionally C A=a million x 4 = 4 B = a million/4 x4 = a million C= a million/2 x 4 = 2 So u have the numbers now and you upload this numbers as a coefficient infron of each team factors. A B C ok + O2 ------> K2O 4K +1O2 ------> 2K2O you may now examine for ur solutions and u can question me yet another question if u have one additionally.:)p.c.