Chemistry: Post your doubts here!

[nehaoscar]

NaOH is basic, so carboxylic acids would react with it. However, alcohols would not.

What about aldehydes and ketones reacting with Na, NaOH and NaHCO3?

 

[Mathemagical]

What about aldehydes and ketones reacting with Na, NaOH and NaHCO3?

Aldehydes and ketones would not react with any of those.

 

[nehaoscar]

How is it A?
B has 3 outer shell e- and each will bond to an F...

 

[Mathemagical]

This is a useful diagram you can refer to.

 

[Mathemagical]

View attachment 54270
How is it A?
B has 3 outer shell e- and each will bond to an F...

A complete outer shell has 8 valence electrons, whereas Boron only has 6 in BF3.

 

[nehaoscar]

Does the equilibrium position affect the rate of reaction?
I'm sure it only affects the yield right?

 

[nehaoscar]

A complete outer shell has 8 valence electrons, whereas Boron only has 6 in BF3.

Then what about B and D? how many electrons do they have in their outer shells?

 

[nehaoscar]

How to do this one? Answer is B

 

[Mathemagical]

Does the equilibrium position affect the rate of reaction?
I'm sure it only affects the yield right?

You're asking the wrong questions here. For every change in temperature, pressure or some other condition you have to know that it may affect one or both of the equilibrium or rate. The answer is D because removing ammonia would not alter the rate, whereas increasing the temperature and pressure would.

 

[nehaoscar]

Answer is C ... how?

 

[Mathemagical]

View attachment 54272

How to do this one? Answer is B

For this, I suggest learning the ICE Tables Method. Here's the link for it: http://tinyurl.com/lv2hlh9

 

[nehaoscar]

Why C? Why not A or B?

 

[nehaoscar]

You're asking the wrong questions here. For every change in temperature, pressure or some other condition you have to know that it may affect one or both of the equilibrium or rate. The answer is D because removing ammonia would not alter the rate, whereas increasing the temperature and pressure would.

But the question specifies forward reaction rate.
Since it is exothermic reaction, wouldn't increasing the temperature increase the backward reaction rate?

 

[Mathemagical]

View attachment 54273
Answer is C ... how?

The question states that vigorous effervescence occurred, so naturally I would opt for C, because Barium is the most reactive element amongst the other choices.

 

[Mathemagical]

But the question specifies forward reaction rate.
Since it is exothermic reaction, wouldn't increasing the temperature increase the backward reaction rate?

This is a trick many students fall for. Increasing the temperature increases both forward and backward rates, but due to the equilibrium position, it would increase the rate of the backward reaction by a relatively larger amount.

 

[nehaoscar]

Why not B? Isn't Cl more reactive than I?

 

[nehaoscar]

Why A?

 

[nehaoscar]

How is 3 correct?

 

[Studydayandnight]

Correct answer is B.

 

[Studydayandnight]

How is the answer D?