Question

Question 1

Which of the following categories of compounds will affect the pH of the aqueous solution they are dissolved in? This assumes they are water soluble. Pick all that apply.

Multiple answers: You can select more than one option

A

alcohols

B

amine

C

aldehyde

D

carboxylic acids

Question 2

Which of the following categories of compounds will be soluble in 5% NaOH (aq) if they are not soluble in water?

A

aldehydes

B

alcohols

C

amines

D

carboxylic acids

Question 3

Which of the following categories of compounds will be soluble in 5% HCl (aq) if not soluble in water?

A

carboxylic acids

B

alcohols

C

amines

D

aldehydes

Question 4

Which of the following IR information is most indicative a compound is an aldehyde or ketone? Note: The question formatting will now allow for super script -1 so the term reciprocal centimeters are used in place of cm^-1

A

strong peaks between 2850-3000 reciprocal centimeters

B

strong sharp peak between 1650-1800 reciprocal centimeters

C

a medium sharp peak at 2250 reciprocal centimeters

D

strong broad peak between 3200-3600 reciprocal centimeters

Question 5

Which of the following IR information is most indicative a compound is a primary or secondary amine? Note: The question formatting will now allow for super script -1 so the term reciprocal centimeters is used in place of cm^-1

A

medium peaks between 3500-3200 reciprocal centimeters

B

strong sharp peak between 1650-1800 reciprocal centimeters

C

strong peaks between 2850-3000 reciprocal centimeters

D

a medium sharp peak at 2250 reciprocal centimeters

Answer 1

Answer 1):-

Option B : "amines" and option D: "carboxylic acids" are correct.

Amines form basic aqueous solution while carboxylic acids form acidic aqueous solution. Alcohols and aldehydes are neutral.

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Answer 2):-

Option D: "carboxylic acids" is correct answer.

Carboxylic acids react with 5% NaOH solution to form salt and water.

R-COOH + NaOH RCOONa + H₂O

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Answer 3):-

Option C : "amines" is correct answer.

Amines react with 5% HCl solution to form ammonium salts.

R-NH₂ + HCl   R-NH₃⁺ Cl^-

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Answer 4):-

Option B : " strong sharp peak between 1650-1800 cm^-1 " is correct answer.

Aldehydes and ketones indicate a strong peak around 1650-1800 cm^-1 due to -C=O bond stretching.

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Answer 5):-

Option A : "medium peaks between 3500-3200 cm​​​​​​​^-1 " is correct answer.

Primary and secondary amines indicate medium peaks at 3500-3200 cm^-1 due to -N-H bonds stretching.

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