Chemistry Gr12 Question

Question

For each of the following situations, identify those for which a reaction is likely to occur. For those that do occur, write a net ionic equation.

a) chromium dipped into silver nitrate

b) gold immersed in hydrochloric acid

c) nickel pellets dropped into calcium acetate, Ca(C2H302)2

d) aluminum dropped into a bath of sulphuric acid

e) zinc dipped into a solution of lead(II) nitrate

Answer 1

Reaction will occur only if the metal added is HIGHER in the activity series than that in soln...see en.wikipedia.org for examples.

a)  Cr(s) +  3AgNO3(aq) ---> 3Ag(s) + (Cr+++)(NO3-)3

b)  NR

c)  NR

d)  2Al(s) + 3H2SO4(aq) ---> 3H2(g) + (Al+++)2(SO4--)3

e)  Zn(s) + Pb(NO3)2(aq) ---> Pb(s) + (Zn++)(NO3-)2

For practice, find a good activity chart and make up your own experiments.

You will find that gold is v low in the series, so is often recovered in production by adding iron or copper to the soln; what other cheap metals could you use?