Can humans use up all the copper in the world

The aldol reaction is catalyzed by acid as well as base. What is the reactive nucleophile in the acid-catalyzed aldol reaction

svp [43]

Answer:

The reactive nucleophile is Ketone.

Explanation:

In organic chemistry, The process of acid - catalyzed aldol condensation starts from when ketone (or any aldehyde) is converted to an -enol, after which it attacks another ketone/aldehyde that has already been activated by parbonyl oxygen protonation.

The process of this is that first of all the ketone undergoes tautomerization to form -enol. Thereafter, the other carbonyl will undergo protonation which makes the carbon activated towards attack. Now, the nucleophilic enol will be added to the carbonyl in a [1,2]-addition reaction and we will now use deprotonation to obtain the neutral Aldol product.

Now, since only the ketone can produce an -enol, thus it is the nucleophile as aldehydes are better electrophiles

4 0

3 years ago

Which of these is a chemical property of a substance?

Ghella [55]

Flamability boiling point color

3 0

4 years ago

Read 2 more answers

Catherine has some seawater. She wants to separate pure water from the seawater.

expeople1 [14]

Answer:

the change is evaporation

Explanation:

the water heats up at the surface of the water and evaporates

4 0

3 years ago

Read 2 more answers

The statement "Although sulfuric acid is a strong electrolyte, an aqueous solution of H2SO4 contains more HSO4− ions than SO42−

PIT_PIT [208]

The statement "Although sulfuric acid is a strong electrolyte, an aqueous solution of H₂SO₄ contains more HSO₄⁻ ions than SO₄²⁻ ions is True. This is best explained by the fact that H₂SO₄ is a diprotic acid where only the first hydrogen completely ionizes.

Why?

H₂SO₄ is a diprotic acid. That means that it has two hydrogen ions to give to the solution. The two dissociation reactions are shown below:

H₂SO₄ + H₂O → HSO₄⁻ + H₃O⁺

HSO₄⁻ + H₂O ⇄ SO₄²⁻ + H₃O⁺

As the arrows show, the first dissociation is complete, meaning that all the sulfuric acid that is present initially is dissociated into HSO₄⁻ and H₃O⁺. However, the second dissociation is incomplete, and it's actually an equilibrium with an acid constant (Ka)of 1.2×10⁻².

That means that if the initial concentration of H₂SO₄ was 1M, the concentration of HSO₄⁻ is going to be 1M as well, but the concentration of SO₄²⁻ is going to be much less than 1M, according to the dissociation constant.

Have a nice day!

4 0

3 years ago

If we have three different solutions, A, B, and C, each containing 100 g of water, plus respectively 6.84 g of sucrose (C12H22O1

GenaCL600 [577]

Answer:

c. A and C have the same boiling point, but B has a lower one.

Explanation:

The freezing point depression is expressed as:

ΔT = kf×m

Where kf is the freezing point depression constant that depends the nature of the solvent and m is molality (mol of solute/kg of solvent)

Boiling point elevation is:

ΔT = kb×m

Where kb is the ebulloscopic constant of the solvent.

As kf, kb and mass of solvent is the same for A, B and C solutions the only difference will be in moles of solute.

A 6,84g of sucrose are:

6,84g× $\frac{1mol}{342,3g}$ = 0,002 moles

B 0,72g of ethanol are:

0,72g× $\frac{1mol}{46,1g}$ = 0,0016 moles

C 0,40g of sodium hydroxide are:

0,40g× $\frac{1mol}{40g}$ = 0,001 moles

Using Van't Hoff factor that describes the number of moles in solution that comes from 1 mole of solute before dissolving, moles in solution for A, B and C are:

A. moles in solution: 0,02 moles×1 = 0,02 moles in solution

B. moles in solution: 0,016 moles×1 = 0,016 moles in solution

C. moles in solution: 0,01 moles×2 = 0,02 moles in solution

As A has the same moles in solution of C, the freezing point depression will be the same in A and C, and the lower freezing point depression will be in B.

Also, the boiling point will be higher in A and C, and then in B.

Thus:

a. C has the lowest freezing point in the group. FALSE. A and C have the lowest feezing point because have the higher freezing point depression.

b. A, B, and C all have different freezing points. FALSE. As moles of A and C are the same, freezing point will be the same for the solutions.

c. A and C have the same boiling point, but B has a lower one. TRUE.

d. The boiling point of C is lower than that of A or B . FALSE. Boiling point of C and A is higher than B.

e. A, B, and C will all have about the same freezing points. FALSE

7 0

3 years ago