The correct IUPAC name of ${\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{CH}\left({\mathrm{CH}}_3\right)-\mathrm{CH}{\left({\mathrm{C}}_2{\mathrm{H}}_5\right)}_2$ is

The correct IUPAC name for the compound CH₃CH₂CH(CH₃)-CH(C₂H₅)₂ is 4-ethyl-3-methylhexane.

Explanation:

• The longest carbon chain contains 6 carbons (hexane).
• Numbering from left to right, substituents are at positions 3 (methyl, CH₃) and 4 (ethyl, C₂H₅).
• According to IUPAC rules, the substituents are arranged alphabetically: 4-ethyl-3-methylhexane.

Final answer:
4-ethyl-3-methylhexane