5 of 20 09
A chemist places zinc metal and hydrochloric acid in a test tube. She observes that the test tube feels warm as hydrogen gas and aqueous zinc chloride
are produced. The reaction follows the unbalanced equation given below.
Zn(s) + HCl(aq) - H20) + ZnCl2(aq) + heat
How do you know whether this is a chemical ct ge or a ysical change?
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Which of the following statements is true? question 4 options: nuclear decay rates vary with the conditions of the reaction, but chemical reaction rates do not. chemical reaction rates vary with the conditions of the reaction, but nuclear decay rates do not. neither chemical reaction rates nor nuclear decay rates vary with the conditions of the reaction. both chemical reaction rates and nuclear decay rates vary with the conditions of the reaction.

Electric charge is what ? a. kinetic energy b. radiation c. discovery d. electricity

Alidded glass container is filled with a colored gas. after a period of time, it is observed that the gas is uniformly spread throughout the box and that the movement has slowed considerably. next, a warm iron plate is carefully placed under the box. why is there resumed movement of the gas in the container?