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MS_SUMTER2010
Apr 27, 2010, 01:42 PM
Predict the products of the reactions below. Then, write the balanced equation and classify the reaction.

A) magnesium bromide + chlorine

mgbr2 + 2cl --->mgcl2 + br2

b) aluminium + iron (iii) oxide

2 al+ 3fe203 ---> 3al203 +2fe3

c) silver nitrate + zinc chloride

zncl2 + 2agno3---> zn (no3)2 +2agcl

d) zinc + hydrocholric acid

zn + 2hcl ---> h2 + zncl2

e) hydrogen peroxide (catalyzed by managanese dioxide)

4h202---> 4h20 +2o2

f) sulfuric acid + sodium hydroxide

h2so4 + 2naso4---> 2h20 + na2so4

g) sodium + hydrogen

na + h---> nah.. Not sure but this what I got

can you help me determine whether its synthesis, decomposition, single replacement, or double displacement

Unknown008
Apr 28, 2010, 07:12 AM
Well, first, I'd really like you to take a little more time to write the formulae properly.

This helps yourself as being a good practice and helps prevent confusion.

These are to be corrected:

a) magnesium bromide + chlorine

mgbr2 + 2cl --->mgcl2 + br2

e) hydrogen peroxide (catalyzed by managanese dioxide)

4h202---> 4h20 +2o2

f) sulfuric acid + sodium hydroxide

h2so4 + 2naso4---> 2h20 + na2so4

g) sodium + hydrogen

na + h---> nah

I hope a) and f) are due to typing errors...
For e), notice that you can divide each compound by 2.
For g), remember that hydrogen is in the form of hydrogen gas, H2.

The equations are:

MgBr_2 + Cl_2 \rightarrow MgCl_2 + Br_2

2H_2O_2\rightarrow 2H_2O +O_2

H_2SO_4 + 2NaOH\rightarrow 2H_2O + Na_2SO_4

2Na + H_2 \rightarrow 2NaH

Remember that:
In synthesis reactions, you generally have several reagents reacting to form a single product. (I'm referring to this part specially wikipedia (http://en.wikipedia.org/wiki/Chemical_synthesis#Other_meanings))

In decomposition reactions, you have one reagent itself forming one or more products, without the need for any other reagent. (wikipedia (http://en.wikipedia.org/wiki/Chemical_decomposition))

In single displacement reactions, one reagent will take one ion from another reagent, leaving the other reagent 'alone'. (wikipedia (http://en.wikipedia.org/wiki/Single_displacement_reaction))

In double displacement reactions, two reagents trade their ions, so that they end up with each other's initial ion. (wikipedia (http://en.wikipedia.org/wiki/Double_displacement_reaction))

Can you try classifying the reactions now? :)

Post what you get.