Chemistry worksheet with matching and naming exercises for organic compounds.

Let’s work through the problem step by step.

We are given two parts:

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Part 1: Match the chemical formulas with their IUPAC names

We have:

a. CH₃NH₂
b. C₂H₅NH₂
c. (C₂H₅)₂NH
d. C₆H₅NH₂
e. (CH₃)₂N

And options:

(i) Ethanamine
(ii) Benzamine
(iii) N-Ethyl Ethanamine
(iv) N,N-Dimethyl methanamine
(v) Methanamine

Let’s match them one by one.

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a. CH₃NH₂

- This is a methyl group (CH₃-) attached to an amine (-NH₂).
- The simplest amine with one carbon → Methanamine
→ So, a matches (v)

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b. C₂H₅NH₂

- Ethyl group (C₂H₅-) attached to -NH₂
- Two-carbon chain amine → Ethanamine
→ So, b matches (i)

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c. (C₂H₅)₂NH

- Two ethyl groups attached to nitrogen, and one H → secondary amine
- Name: Each ethyl group is “ethyl”, and since it’s on nitrogen, we say “N-ethyl” for each? Wait — actually, the correct name is N-Ethyl ethanamine? Let’s think.

Actually, standard IUPAC: When you have two identical alkyl groups on nitrogen, you use “di”. But here, the base chain is ethane (from one ethyl), and the other ethyl is a substituent on nitrogen → so N-Ethyl ethanamine

Yes → c matches (iii)

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d. C₆H₅NH₂

- C₆H₅ is phenyl group → attached to NH₂ → this is commonly called aniline, but IUPAC also accepts Benzenamine or Benzamine

Looking at options, (ii) is Benzamine → so d matches (ii)

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e. (CH₃)₂N

Wait — this looks incomplete. It should be (CH₃)₂NH or (CH₃)₃N?

But in the answer key provided later, it says:

> e. (CH₃)₂N → (iv) N,N-Dimethyl methanamine

That suggests it’s meant to be (CH₃)₂NH? Or perhaps (CH₃)₃N?

Wait — let’s check the answer key shown in the image:

In “Ans1.Match the following”:

It shows:

a. CH₃NH₂ → (v) Methanamine
b. C₂H₅NH₂ → (i) Ethanamine
c. (C₂H₅)₂NH → (iii) N-Ethyl Ethanamine
d. C₆H₅NH₂ → (ii) Benzamine
e. (CH₃)₂N → (iv) N,N-Dimethyl methanamine

But (CH₃)₂N is not a complete molecule — it’s missing a hydrogen or another group.

However, if we assume it’s (CH₃)₂NH, then that would be N-Methyl methanamine? No — wait:

Actually, (CH₃)₂NH is N-Methylmethanamine? That doesn’t sound right.

Standard naming:

- CH₃NH₂ → Methanamine
- (CH₃)₂NH → N-Methylmethanamine? Actually, no — IUPAC calls it N-Methylmethanamine only if you consider one methyl as parent and the other as substituent.

But more accurately, (CH₃)₂NH is Dimethylamine, and IUPAC name is N-Methylmethanamine? Hmm.

Wait — let’s look at option (iv): N,N-Dimethyl methanamine

That would imply three methyl groups: two on nitrogen, and one from “methanamine” → that would be (CH₃)₃N → trimethylamine.

Ah! So probably, e. (CH₃)₂N is a typo and should be (CH₃)₃N

Because:

- (CH₃)₃N → three methyl groups on nitrogen → N,N-Dimethylmethanamine? Wait, no — if parent is methanamine (one carbon), then two methyls on nitrogen → N,N-Dimethylmethanamine

Yes — that makes sense.

So even though written as (CH₃)₂N, it’s likely meant to be (CH₃)₃N → which is N,N-Dimethylmethanamine

So e matches (iv)

Thus, matching is:

a → v
b → i
c → iii
d → ii
e → iv

Which matches what’s shown in Ans1.

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Part 2: Write the IUPAC name of following

a. C₆H₅-NH-CH₃
b. CH₃-NH-C₂H₅
c. (C₆H₅)₂-N-CH₃

From the answer key:

a. N-Methylaniline
b. N-Methylethanamine
c. N-Methyl N-phenylaniline

Let’s verify.

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a. C₆H₅-NH-CH₃

- Phenyl group attached to NH, which is also attached to methyl.
- Parent can be aniline (C₆H₅NH₂), and methyl substituent on nitrogen → N-Methylaniline
→ Correct

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b. CH₃-NH-C₂H₅

- Methyl and ethyl groups on nitrogen → secondary amine
- Choose longer chain as parent → ethyl → so parent is ethanamine
- Methyl group on nitrogen → N-Methylethanamine
→ Correct

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c. (C₆H₅)₂-N-CH₃

- Two phenyl groups and one methyl group on nitrogen
- Parent? Since phenyl is aromatic, often named as derivative of aniline.
- But with two phenyls, it’s N-phenyl-N-phenylmethanamine? Not common.

Common name: N-Methyl-N-phenylaniline? But aniline has one phenyl already.

Actually, standard IUPAC: The compound is N-Methyl-N-phenylbenzenamine? Or better: N,N-Diphenylmethanamine? No.

Wait — (C₆H₅)₂N-CH₃ → two phenyls and one methyl on N.

IUPAC name: N-Methyl-N-phenylbenzenamine? But that implies one phenyl is part of parent.

Better: Since benzene ring is preferred, take one phenyl as parent → benzenamine, then N-methyl-N-phenyl → so N-Methyl-N-phenylbenzenamine

But in the answer key, it says N-Methyl N-phenylaniline

“Aniline” is common name for benzenamine, so N-Methyl-N-phenylaniline is acceptable, though technically redundant (since aniline already has one phenyl).

But in many contexts, it’s used.

Alternatively, N,N-Diphenylmethanamine — but that would be if methyl is parent.

Actually, IUPAC prefers the larger group as parent. Phenyl is larger than methyl, so parent should be benzenamine.

With two substituents on nitrogen: methyl and phenyl → so N-Methyl-N-phenylbenzenamine

But the answer key says N-Methyl N-phenylaniline — which is essentially the same, using “aniline” instead of “benzenamine”.

So we’ll go with that.

Thus, all answers match the provided key.

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Final Answer:

1. Matching:
a → (v)
b → (i)
c → (iii)
d → (ii)
e → (iv)

2. IUPAC Names:
a. N-Methylaniline
b. N-Methylethanamine
c. N-Methyl N-phenylaniline