I think it is the third statement
‘A unit is made up of two or more atoms’
Amber preserves animals in dried tree sap
Answer:
your answer is (a) Copper Metal
Explanation:
Answer:
D
Explanation:
We must study the reaction pictured in the question closely before we begin to attempt to answer the question.
Now, the reaction is a free radical reaction. This implies that only one electron is transferred. The transfer of one electron is shown using a half arrow rather than a full arrow. The both species are radicals (odd electron species) and contribute one electron each.
Hence we must show electron movements in both species using a half arrow.
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.
Learn more about chemical change here:
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