15. Which reaction produces a coloured substance? A. The addition of sodium metal to water.
B. The addition of sulfur dioxide gas to water.
C. Burning sodium metal in chlorine gas.
D. The addition of chlorine gas to a solution of potassium iodide.

A color change may also indicate that a chemical reaction has occurred. A reaction has occurred if two solutions are mixed and there is a color change that is not simply the result of a dilution of one of the reactant solutions. A color change may also occur when a solid and liquid are mixed.

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Ithe undersigned only for use your own email and delete any and copies and of the itself and to be there is a good timewhat does a decrease in temperature indicate about the molecules in a sample of liquid water? decreased chemical energy of the moleculesdecreased kinetic energy of the moleculesincreased chemical energy of the moleculesincreased kinetic energy of the moleculeshow does a sample of helium at 15 â°c compare to a sample of helium at 215 k? the helium at 15 â°c has a higher average kinetic energy than the sample at 215 k.the helium at 15 â°c has lower nuclear energy than the sample at 215 k.the helium at 15 â°c has slower-moving atoms than the sample at 215 k.the helium at 15 â°c has smaller atoms than the sample at 215 k.