Which of these types of changes is a physical change? A. Breaking apart one substance into two substances
B. Dissolving one substance in another
C. Changing one substance into another
D. Making a new substance
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Aglow stick contains a glass vial with chemicals. when the glow stick is bent, the vial breaks and the chemicals react to produce a glow. a science student observes that a glow stick kept in the freezer glows for a longer duration than a glow stick kept at room temperature. what conclusion can be drawn based on the observation? be sure to note the outcome and test variables in the conclusion.

Which buffer would be better able to hold a steady ph on the addition of strong acid, buffer 1 or buffer 2? explain. buffer 1: a solution containing 0.10 m nh4cl and 1 m nh3. buffer 2: a solution containing 1 m nh4cl and 0.10 m nh3

Consider the following reaction at equilibrium. 2co2 (g) 2co (g) + o2 (g) h° = -514 kj le châtelier's principle predicts that the equilibrium partial pressure of co (g) can be maximized by carrying out the reaction a. at high temperature and high pressure b. at high temperature and low pressure c. at low temperature and low pressure d. at low temperature and high pressure e. in the presence of solid carbon