Cooling a substance causes molecules to slow down and get slightly closer together, occupying a smaller volume that results in an increase in density. ... Cold water is more dense and will sink in room-temperature water.
Physical and chemical changes are reversible and nonreversible changes. The release of carbon dioxide gas indicates a chemical change.
<h3>What is a chemical change?</h3>
A chemical change is a change in which a new substance is produced when the reactants react in the reaction mixture. The chemical produced cannot be reversed back to the reactants and hence, it is nonreversible.
The release of carbon dioxide is a chemical change as limestone and hydrochloric acid react with each other chemically and as a result, a new substance was formed.
Therefore, the production of carbon dioxide indicates a chemical change.
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<span>systems are involved in this process, How are they involved?
The way that you touching </span><span> a hot pan and yanking your hand away is your body saying that "Aye, This isn't right" and our nerves go to the source where you had touched the hot pan... sending the signals to your brain, Your hand might have a small blister..the reason why that is, because its your bidy naturally healing its self with an internal wound</span>
The scientific notation should specific the significant digits. So it to write like x.xx * 10 ^ x. So the answer is 6.421 * 10 ^3.
