Acid/Base

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Dencology

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Which of the following statements on acid base reactions involving organometallic compounds are CORRECT? I. Diethyl ethers are commonly used as reaction solvents. II. Bronsted-Lowry reactions are carried out in the presence of hydroxyl, -OH bearing compounds. III. Hydroxyl, -OH bearing compounds in the reaction act as Bronsted bases. IV. Organometallic compounds in the reaction act as Bronsted bases.

guys the answer is I,II,IV. i just don't understand choice III. Bronston base accept H so OH can accept proton to become H2O? can you explain?

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Which of the following statements on acid base reactions involving organometallic compounds are CORRECT? I. Diethyl ethers are commonly used as reaction solvents. II. Bronsted-Lowry reactions are carried out in the presence of hydroxyl, -OH bearing compounds. III. Hydroxyl, -OH bearing compounds in the reaction act as Bronsted bases. IV. Organometallic compounds in the reaction act as Bronsted bases.

guys the answer is I,II,IV. i just don't understand choice III. Bronston base accept H so OH can accept proton to become H2O? can you explain?

I cant see aww my eyes :eek:
 
Which of the following statements on acid base reactions involving organometallic compounds are CORRECT? I. Diethyl ethers are commonly used as reaction solvents. II. Bronsted-Lowry reactions are carried out in the presence of hydroxyl, -OH bearing compounds. III. Hydroxyl, -OH bearing compounds in the reaction act as Bronsted bases. IV. Organometallic compounds in the reaction act as Bronsted bases.

guys the answer is I,II,IV. i just don't understand choice III. Bronston base accept H so OH can accept proton to become H2O? can you explain?

The problem isn't talking about hydroxide ions, it's talking about alcohols ("hydroxyl, -OH bearning compounds") In III, when you react an organometallic agent with an alcohol, the alcohol will donate the proton to the organometallic agent, therefore it is a bronstead acid, not base.
 
sorry i always get a little confused when it comes to bronsted lowry vs lewis acid/bases.

what exactly is the difference between the two? lewis acid/base is only used for coordinate covalent bonds? and bronsted lowry acid/bases are proton donors and proton acceptors respectively?

if that is so, you can't reword this question in terms of lewis acid/bases right? cuz they only work for coordinate covalent bonds where one donates electrons and one accepts electron pair?
 
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sorry i always get a little confused when it comes to bronsted lowry vs lewis acid/bases.

what exactly is the difference between the two? lewis acid/base is only used for coordinate covalent bonds? and bronsted lowry acid/bases are proton donors and proton acceptors respectively?

if that is so, you can't reword this question in terms of lewis acid/bases right? cuz they only work for coordinate covalent bonds where one donates electrons and one accepts electron pair?

When you're talking about Lewis acids and bases, a lewis acid is an electron pair acceptor and a lewis base is an electron pair donor. You're correct in saying that Bronsted acid/base are proton donor/acceptor, respectively.

I think that when talking about acid/base reactions, you're almost always using the Bronsted-Lowry definition of an acid/base. When you talk about about Lewis acids, you're dealing with reactions where an electron pair is donated but no proton transfer occurs.

For example, let's say an organometallic compount like CH3MgBr reacts with a ketone. The grignard reagent donates its electron pair to the ketone, therefore the grignard reagent is an electron pair donor (Lewis base) and the ketone is the electron pair acceptor (Lewis acid). But you can't say that the ketone is a Bronsted-Lowry acid because it's not a proton.

You can also think about it this way... a lewis acid is an electrophile and a lewis base is a nucleophile.
 
so in the above question, CH3MgBr, the organometallic compound acts as a bronsted lowry base while the CH3 acts as a lewis acid?
 
so in the above question, CH3MgBr, the organometallic compound acts as a bronsted lowry base while the CH3 acts as a lewis acid?

If you're talking about the original question, the lewis acid is the H+... I think, not totally sure.
 
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