Although this bottle is labeled vinegar,  no fizzing occurred when some of the liquid in it was added to powder from this box labeled baking soda.  But when an acidic liquid such as vinegar is added to baking soda the resulting mixture fizzes, so this bottle clearly has been mislabeled.
A flaw in the reasoning in the argument above is that it assumes that the fact of a labeling error is proof of an intention to deceive.