Which is the smallest particle into which water (h2o) in a glass can be broken down and still remain water? a. a water molecule b. only an oxygen atom c. only a hydrogen atom d. a hydrogen peroxide molecule

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Which of the following is an indication that a substance has undergone a chemical change? a. no new product has been formed. b. the color of the substance has not changed. c. the original constitute has not changed. d. the molecular structure has changed.

Match the formula for the following compound:   magnesium sulfate heptahydratemgs·7h2omg2so4·7h2omg(so4)2·7h2omgso4·7h2o