X equals <span>2.76923076923</span>
Answer:
Calcium carbonate reacts with hydrochloric acid to form carbon dioxide gas. 2HCl (aq) + CaCO 3(s) CaCl 2 (aq) + CO 2(g) + H 2 O (l).
<span>Physical change, heat caused this.
Water molecules that only vibrate are in solid form. If heat energy is added, the molecules will speed up their vibrations until they can break loose from the organized pattern of a solid and begin to slide over each other, changing to liquid state. If more heat energy is added, the molecules will speed up more and move randomly in all directions as a gas/vapor. Removing heat energy will reverse these changes.
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Melting? not really sure what type of answer they are going for but the substance is going through the melting phase
*base
a base is added to an acid to neutralize it.
