Question

Which of the following is not an oxidation-reduction reaction?

A. Ca + 2 HCl ---> CaCl2 + H2
B. H2 + Cl2 ---> 2 HCl
C. NaCl + LiNO3 ---> NaNO3 + LiCl
D. 2 CO + 2 NO ---> 2 CO2 + N2

lol need help 8D!!

Answer 1

for each reaction, write the oxidation state of each element.
then see if the oxidation state increases or decreases on going from left to right

if it remains the same, then that element is neither oxidized or reduced in the reaction
that means that reaction is neither an oxidation nor reduction reaction

Answer 2

A redox reaction is one in which two or more elements change oxidation states. In order to identify a redox reaction, start by assigning oxidation numbers to each element and see if any change.

Co(OH)2(s) + 2HCl(aq) --> CoCl2(aq) + 2H2O(l) .... Not redox, no oxidation number changes. This one is double replacement, or acid-base. Take your pick. Acid-base neutralization reactions are a type of double replacement.

Ca(s) + 2HCl(aq) -->CaCl2(aq) + H2(g)
Fe(s) + 2AgNO3(aq) --> Fe(NO3)2(aq) + 2Ag(s)
Both of these are redox. Calcium and iron metals are initially in the zero oxidation state and they are each oxidized to the +2 oxidation state, while hydrogen and silver are reduced to the elemental form.

NH3(aq) + H2O(l) <==> NH4+(aq) + OH−(aq) ... not redox. Not even much of a reaction. The equilibrium will lie far to the left. Only a very few molecules of ammonia will actually react with water.

Cl2(g) + H2O(l) --> H+(aq) + Cl−(aq) + HOCl(aq) ... redox. Cl2 undergoes a disproportionation reaction in which chlorine in Cl2 is both oxidized to +1 in HOCl, and reduced to Cl- where the oxidation number is -1.

Answer 3

hope this helps