Zinc (Zn) reacts with hydrochloric acid (HCI) and produces hydrogen

gas. This is an example of:

A. A new substance is formed

B. A change in composition at the atomic level.

C. All of these

D. A chemical change.

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Consider three 10g samples of water: one as ice, one as a liquid, and one as a vapor. How does the volume of the vapor sample compare with the other?

Which two locations are MOST probable for locating the cloud of electrons?

If the gravity on a planet decreases, what happens to the weight of an object on that planet

When an atom loses an electron, what does it become? a. A positive ion b. A neutral ion c. A negative ion d. A neutral atom

Which chemical formula represents a diatomic molecule? answers?

Number of hydrogen atoms in NaC2HO4

Calculate the pH for an acid that has a [H+] of 5.8 x10^-11 M.

Complete the lewis dot structure for h2co (in which both h atoms are bonded to c).

Do substances have to be cold to freeze?

Which statement is true of the carbon atoms that make up a diamond? A. They can slip past one another slowly. B. They are always vibrating in place. C. They vibrate only when they are heated. D. They are locked in place and do not move at all.