Give an example of a situation where a color change occurs, but not because of a chemical reactions?

Fossil fuels are organic compounds that are made from

If you burn 46.6 g of hydrogen and produce 416 g of water, how much oxygen reacted

In an exothermic reaction at equilibrium, what is the effect of lowering the temperature? a. the reaction makes more products. b. the reaction makes more reactants. c. the reaction is unchanged.