The correct answers are options C, that is, silver tarnishes and becomes black when exposed to oxygen, and option E, that is, diesel fuel burns when it is heated.
Chemical changes refer to the modifications in which the chemistry at molecular level is modified as the initial substance gets transformed into a new and different final substance. This change occurs with the dissociation of old bond and production of new bonds respectively.
Silver gets tarnished and becomes black when exposed to oxygen. This refers to a chemical change as silver a white and lustrous substance gets transformed into a tarnish black final substance. However, silver does not easily react with oxygen at usual circumstances. It easily reacts with sulfur comprising components in the air and generates black compound as Ag₂S.
Burning of diesel fuel when it is heated. Diesel refers to a mixture of hydrocarbons varying approximately from C₁₀H₂₀ to C₁₅H₂₈. When these hydrocarbons get burnt they generate novel substances, that is, carbon dioxide and water. Hence, it is also a chemical reaction.
If a person weighs 63.4 KG they will weigh 139.773 but if you estimate it which in most cases you do it would be 139.8 :)
Answer:
the atoms of the original substances gain, lose and even share their very own electrons. write the symbols of the elements that form the compound. Write down the valency, and lastly go over valencies. This is all I got so far. I hope this helps
Explanation:
They are both made up of the same protein called "histones".
Answer:

Explanation:
Hello!
In this case, since calcium's oxidation state when forming ionic bonds is +2 and sulfur's oxidation state when bonding those bonds is -2, for the required formula we write:

Now, since they have the same charge number, we infer the ionic compound formed when they bond is calcium sulfide:

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