Open QuestionWhen a substance changes states (melts, evaporates, etc.) it is often what type of change?397views
Open QuestionWhich actions are evidence that a chemical reaction has occurred? Check all that apply.540views
Open QuestionWhich of the following is an example that includes evidence of a chemical change?429views
Open QuestionA piece of limestone erodes due to acid rain. this process can be best described as a331views
Open QuestionAcid rain hits a statue. Over time holes are formed in the statue. This is an example of418views
Open QuestionIf two substances are mixed and a new substance is formed, what type of change is it?743views