Students are baking a cake. They mix together all the necessary ingredients and pour them into a pan. Then they place the pan into the oven to cook for 40 minutes.
Which statement BEST explains why baking a cake is evidence of a chemical reaction?
1.The state of matter of some of the ingredients changed while being cooked.
2.The ingredients formed a new substance after they were cooked in the oven.
3.The temperature of the ingredients increased as they absorbed thermal energy from the oven.
4.The total mass of the ingredients was the same before and after they were cooked.