Question

1.What is the function of ethanol in this aldol condensation?

A.Ethanol is the solvent for the reaction.

B.None of the answers shown are correct.

C.Ethanol is used to remove a proton from the carbonyl group of 3,4-dimethoxybenzaldehyde.

D.Ethanol is the recrystallization solvent.

2.Assume the two reactants were in equimolar amounts to begin with but you used 2.0 g of 1-indanone in the reaction instead of 0.20 g, how might this affect your final yield?

A.Yield would be doubled.

B.YIELD WOULD NOT BE AFFECTED

C.YIELD WOULD DECREASED BY A FACTOR OF 10

D. YIELD WOULD INCREASE BY A FACTOR OF 10

3.Assume the sodium hydroxide has been setting out on the lab bench open to the atmosphere for a period of time before you add it to the test tube. How might this affect your yield?

A. YIELD WOULD LIKELY DECREASE

B. YIELD WOULD INCREASE

C. YIELD WOULD NOT BE AFFECTED, BUT RATE OF REACTION WOULD DECREASED

D. YIELD WOULD NOT BE AFFECTED

4.What might be the result if you did not use enough hydrochloric acid and the final pH remained above 7?

A.Yield would remain the same, but purity of the product would decrease.

B.Yield would likely increase and the purity of the product would increase.

C.Yield would remain the same, but purity of the product would increase.

D.Yield would likely decrease and the purity of the product would decrease.

5.What might be the result if you did not grind the two initial reactants sufficiently?

A.Yield would decrease, but purity would not be affected.

B.Both yield and purity would decrease.

C. Yield would not be affected, but purity would be decreased.

D. Neither yield nor purity would be affected.

6.To what does the term \'aldol\' refer in aldol condensation?

A. The formation of a product from aldehyde and alcohol reactants.

B. The formation of a carboxylic acid.

C. An EAS mechanism.

D. The reactants both contain the aldehyde and alcohol functional groups.

Answer 1

Answer –

1) A.Ethanol is the solvent for the reaction.

We know aldol condensation means the formation of new carbon-carbon bond with forming aldehyde and alcohol in the same molecule for product. This reaction carried out in the ethanol, so ethanol is solvent.

2) B.YIELD WOULD NOT BE AFFECTED

We know the yield of the product is depends on the limiting reactant, when there are both reactant required in the same amount and if one is more than required , then there is no any effect on the product. If there is less than required one then there is effect on the yield of the product.

3) A. YIELD WOULD LIKELY DECREASE

We know NaOH is gets hygroscopic when we placed in the atmosphere, so when we added add it to the test then the concentration of NaOH is not correct, means NaOH concentration will be less than accepted and that will effect on the reaction product and product will be less.

4) D.Yield would likely decrease and the purity of the product would decrease.

When we didn’t use the enough hydrochloric acid and the final pH remained above 7 then there is acidic condition and reaction is not carried out completely with there is impure product will be formed

5) B.Both yield and purity would decrease.

If we did not grind the two initial reactants sufficiently then there is reaction rate gets slow and there is less chance for the complete reaction and there is remaining reactant in solution. So there is reactant and product are in solution, so yield gets decreased and also it effect on purity.

6) A. The formation of a product from aldehyde and alcohol reactants.

We know aldol means the aldehyde and alcohol, when there are two aldehyde groups reacted to each other there is formation of aldehyde and enolate as reactant, so in the reactant there are both aldehyde and alcohol, but aldol mean the product of these both reactant.