Chapter 26

Question 1

which are the carbonyls

Answer 1

aldehydes - al

ketones - one

Question 2

solubility of aldehydes?

solubility of ketones?

Answer 2

soluble because can form hydrogen bonds with water
O in carbonyl
H in water

Question 3

why can carbonyl react at all?

Answer 3

C = O bind is polarised
because oxygen is much more electronegative than carbon
Cs+
Os-

Question 4

oxidation of carbonyls

Answer 4

aldehydes can be oxidised
ketones cannot

Cr2O7 2- REDUCED TO Cr3+
orange to green

Question 5

test for aldehydes

• how is the testing substance made
• what is the active substance
• conditions?
• what happens?
• observation?

Answer 5

• Tollens reagent
• mix aqueous ammonia and silver nitrate
• [Ag(NH3)2]+
• heat gently
• become carboxylic acid, silver ions reduced to silver atoms
• silver mirror forms coating test tube