Answer:
The prefix is but-.
Explanation:
"A molecule of a compound contains a total of 10 hydrogen atoms and has the general formula CnH2n+2. Which prefix is used in the name of this compound?
A) but- B) dec- C) oct- D) pent"
Hydrocarbons are compounds that contain only carbon and hydrogen. They are divided into aliphatic and aromatic hydrocarbons.
In aliphatic hydrocarbons, carbon atoms form open chains and are classified as alkanes, alzenes or alkenes, and alcines or alkynes.
Alkanes have only simple bonds between carbon atoms. The general formula for aliphatic (straight-chain) alkanes is CₙH₂ₙ₊₂.
Alkenes are hydrocarbons that have a carbon-carbon double bond in their molecule, and that is why they are called unsaturated. The generic formula is CₙH₂ₙ.
Alkynes have a triple bond between two carbon atoms. Its general formula is CₙH₂ₙ.
So in this case, you know that it is an alkane. To name an alkane, you must know the number of carbons n. For that you know that the compound has 10 hydrogens. That is, 2n + 2 must be 10. Then you can calculate the value of n:
2*n+2=10
2*n=10 -2
2*n=8
n=8÷2
n=4
So, in this case, the prefix is but-.