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lutik1710 [3]
3 years ago
7

Which of the following describes a physical property? A) gunpowder explodes B) when two substances are mixed with a precipitate

forms C) a substance change colors when heated, but changes back when cooled D) a candle burns
Chemistry
2 answers:
never [62]3 years ago
6 0

Answer is: C) a substance change colors when heated, but changes back when cooled.

Physical property can be observed and measured without any changes in molecular composition. The same substance is present before and after the change.

Gunpowder explosion, precipitate form and candle burn are chemical change (chemical reaction combustion), because new substances are formed, the atoms are rearranged and the reaction is followed by an energy change (exothermic reaction because energy is released).

ValentinkaMS [17]3 years ago
5 0
The correct answer is C) A substance changes color when heated, but changes back when cooled. Hope this helps.
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It's important to make sure you completely understand the terms of conjugate base, conjugate acid, pKb, pKa, and how they all relate. It's easy to mix up the meanings of these definitions.

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