Final answer:
The fallacy used in the statement about baking powder's toxicity is termed 'begging the question,' which occurs when someone assumes a controversial point is true without proof. Chemically, baking powder, which produces carbon dioxide when mixed with water, is not toxic.
Step-by-step explanation:
The fallacy in the statement "Baking powder is toxic. How could you doubt that?" is called begging the question. This occurs when a person assumes the truth of something controversial while trying to prove their conclusion, without providing any evidence or logical reasoning.
In terms of the chemistry behind baking powder, it is not inherently toxic. Baking powder consists of baking soda (sodium hydrogen carbonate) and a solid acid such as potassium hydrogen tartrate (cream of tartar), amongst other ingredients. When baking powder is mixed with water, the acid reacts with sodium hydrogen carbonate to produce carbon dioxide gas, which causes the fluffiness in baked goods.
A nonchemical understanding can be related to adding eggs to a brownie mix, as per the balanced equation for brownie preparation, which is a process familiar to many. The statement about the toxicity of baking powder is misleading and unsupported, much like a non-factual claim that a specific brand of cereal could cause healthy weight without any evidence.