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When the chemicals iron sulfide (fes) and hydrochloric acid (hcl) are combined, bubbles appear from the mixture. 1. does the appearance of bubbles indicate a physical or chemical change? 2. why do the bubbles indicate this change? 3. what property is this?

Which of the following is not a characteristic of s waves?

These traits describe either a chemical or a nuclear reaction. which statements describe a nuclear reaction? check all that apply. involves the loss, gain, or sharing of electrons may involve a change in total mass involve relatively low energy changes occur outside the nucleus involve very high-energy changes involve changes in nuclides when decay occurs