Select the following statements that are true. select all that apply.
a. hydrocarbons contain only c and h atoms.
b. names of organic compounds consist of a root for the longest chain, a prefix for any attached group, and a suffix for the type of compound.
c. isomers are compounds with the same molecular formula but different properties.
d. alkynes contain single bonds; alkenes triple bonds and alkanes double bonds.
e. the longer the carbon chain the lower the molar mass and the lower the intermolecular contact, the lower the dispersion forces.

The statements which are true among these are: (a),(b) and (c) because,

(a) The simplest organic compounds which contains only carbon and hydrogen atoms are called hydrocarbons.

(b) The IUPAC naming of organic compounds have some rules for the naming of compounds, which consists of

And lastly a suffix for the type of bond that molecule have.

(c) Isomers are the compound which same same molecular formula but different arrangement of molecules, due to this different arrangement they have different physical and chemical properties.

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.