Test tube reactions

Question 1

What is the test for an alkene?

Answer 1

Shake with bromine water

Question 2

What is the test for an halogenoalkane?

Three stages

Answer 2

1) Add NaOH (aq) & warm
2) Acidify with HNO3
3) Add AgNO3 (aq)

Question 3

What is the test for an alcohol?

Answer 3

Add acidified K2Cr2O7

Question 4

What is the test for an aldehyde?

Answer 4

Warm with Fehling’s solution

Or

Warm with Tollens’ reagent

Question 5

What is the test for an carboxylic acid?

Answer 5

Add NaHCO3 (aq)

Question 6

What would you see for a positive test with shaking an alkene with bromine water?

Answer 6

The orange colour would disappear

Question 7

What would you see for a positive test with the test for an halogenoalkane?

Answer 7

Precipitate of AgX

Question 8

What would you see for a positive test with distilling an alcohol with K2Cr2O7?

Answer 8

The orange colour turns green with primary and secondary alcohols

Question 9

What would you see for a positive test with aldehydes and the Fehling’s test?

Answer 9

Blue colour turns into a red precipitate

Question 10

What would you see for a positive test with Tollens’ solution?

Answer 10

Silver mirror forms

Question 11

What would you see for a positive test with carboxylic acids and NaHCO3?

Answer 11

Effervescence (CO2 given off)