Question #e0b9c

1 Answer
Feb 5, 2016

Answer:

Reactions #"(i)"# and #"(ii)"#.

Explanation:

I admit that I've never come across reactions #"(iii)"# and #("iv")#, so right from the start I eliminated those two as possible valid answers.

Now, the first reaction will indeed produce carbon monoxide, #"CO"#.

When heated with concentrated sulfuric acid, potassium ferrocianide, #"K"_4"Fe"("CN")_6#, will produce

  • potassium sulfate, #"K"_2"SO"_4#
  • iron(II) sulfate, #"FeSO"_4#
  • ammonium sulfate, #("NH"_4)_2"SO"_4#
  • carbon monoxide, #"CO"#

The balanced chemical equation for this reaction looks like this

#"K"_4"Fe"("CN")_text(6(aq]) + 6"H"_2"SO"_text(4(aq]) + 6"H"_2"O"_text((l]) -> 2"K"_2"SO"_text(4(aq]) + "FeSO"_text(4(aq]) + 3("NH"_4)_2"SO"_text(4(aq]) + 6"CO"_text((g]) uarr#

Now, I assume that the second reaction is actually the decomposition of nickel tetracarbonyl, #"Ni"("CO")_4#, since no other reactants are given.

Upon heating, nickel tetracarbonyl will decompose to form nickel metal and carbon monoxide. The balanced chemical equation for this reaction looks like this

#"Ni"("CO")_text(4(g]) stackrel(color(red)(Delta)color(white)(aa))(->) "Ni"_text((s]) + 4"CO"_text((g])#

This reaction is part of the Mond process, a technique used to extract nickel from impure nickel.

As far as the other two reactions go, I really don't see what could be going on there.

The only way I can think off to getting carbon monoxide from a zinc compound is by heating zinc oxide, #"ZnO"#, with carbon. The reaction will produce carbon monoxide and zinc vapor

#"ZnO"_text((s]) + "C"_text((s]) stackrel(color(red)(Delta)color(white)(aa))(->) "Zn"_text((g]) + "CO"_text((g])#

I assume that the last reaction involves heating magnesium carbonate with zinc metal. I don't think that adding zinc in there could change the fact that magnesium carbonate decomposes to form magnesium oxide, #"MgO"#, and carbon dioxide, #"CO"_2#.