The number of primary (1°), secondary (2°), tertiary (3°) and quaternary (4°) carbon atoms present in the structure of 3-ethyl-2,2,4-trimethylpentane are respectively :

Step-by-step solution

The structure of 3-ethyl-2,2,4-trimethylpentane is: CH ₃- C ( CH ₃)₂- CH ( CH ₂ CH ₃)- CH ( CH ₃)- CH ₃ Primary (1°) carbons are the terminal methyl groups: C1, C5, two methyls on C2, one methyl on C4, and the terminal carbon of the ethyl group. Total = 6. Secondary (2°) carbon is the - CH ₂- group of the ethyl substituent. Total = 1. Tertiary (3°) carbons are C3 and C4, as each is attached to three other carbons. Total = 2. Quaternary (4°) carbon is C2, as it is attached to four other carbons. Total = 1. Thus, the