Balancing the reaction by oxidation number method k2cr2o7+sncl2+hcl

Explanation:

The products of this reaction are given by:

Firstly, dichromate anion becomes chromium(III) cation, let's write this change:

The following steps should be taken:

Similarly, tin(II) cation becomes tin(IV) cation:

Now that we have the two half-equations, multiply the second one by 3, so that it also has 6 electrons that will be cancelled out upon addition of the two half-equations:

Add them together:

Adding the ions spectators:

it's all four options.