Can someone help me?

For each of the following, predict whether or not a reaction will occur and balance the equation. If the reaction will not occur, write NR. But if it does, then write the complete equation and balance it.

a) Al(s) + KNO3(aq) -->

b) Al(s) + NiCl3(aq) -->

c) Ni(s) + Hg2(NO3)2(aq) -->

2 Answers
May 10, 2018

a) NR
b) #Al(s) + NiCl_3(aq) rarr AlCl_3 + Ni#
c) #Ni(s) + Hg(NO_3)_2(aq) rarr Ni(NO_3)_2 + Hg#

Add phase states.

Explanation:

a) #Al#(s) + #KNO_3#(aq) will not occur, as aluminum is not as reactive as potassium.

b) Since aluminum is more reactive than nickel, this reaction occurs.
#Al(s) + NiCl_3(aq) rarr AlCl_3 + Ni#

c) Since nickel is more reactive than mercury, this reaction occurs.
#Ni(s) + Hg(NO_3)_2(aq) rarr Ni(NO_3)_2 + Hg#

Note: I'm assuming the nickel in the 3rd equation is a +2 ion.

You'll need to supply the phases states yourself.

May 11, 2018

Refer to the explanation.

Explanation:

These reactions are all possible single replacement (single displacement) reactions involving metals. In order to determine whether these reactions actually occur, we must compare the reactivity of each metal in relation to one another using a metal reactivity series. A very comprehensive series can be found at:

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

A metal will replace another metal in a compound only if it is above the other metal in the series, which means it is more reactive. Refer to the reactivity series for each reaction. I'm not going to add it to the explanation box because it is very large. Just click on the link.

#"a)"# #"Al(s)" + "KNO"_3("aq")##rarr##"NR"#

Potassium is at the top of the reactivity series, so aluminum is less reactive than potassium, and the reaction will not take place.

#"b)"# #"Al(s)" + "NiCl"_3("aq")"##rarr##"Ni(s)" + "AlCl"_3("aq")"#

This reaction will occur because aluminum is above nickel in the reactivity series, so it is more reactive and will replace the nickel in the #"NiCl"_3"# compound. I really think the nickel compound should be #"NiCl"_2"#, but since your instructor gave it as #"NiCl"_3"#, I used that in the equation.

#"c)"# #"Ni(s)" + "Hg"_2"(NO"_3)_2("aq")"##rarr##"2Hg("l") + Ni(NO"_3)_2("aq")"#

This reaction will occur because nickel is above mercury in the reactivity series, so it is more reactive and will replace the mercury in the #"Hg"_2"(NO"_3)_2"# compound.