4.) which organic compound has five carbon atom with at least one double bond? O pentyne
O pentene
O pentane
O butene

The answer is pentene.

Explanation:

The nomenclature for an organic compound with 5 carbon atoms will have a  -pent prefix.

An organic compound with at least one double bond will have alkene suffix, which is -ene.

Thus, the nomenclature for an organic compound that has 5 carbon atoms with at least one double bond will be pentene.  

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

explanation:

thats how its supposed to be