@Zupari Can you give me some exercises related to mole calculation and the like? I am especially weak in this topic of Chemistry :/

Question

anonymous · Answer

Well do you need some serious problems or normal ones?

kc_kennylau · Answer

As you like, b/c I'm learning Chemistry by myself.

kc_kennylau · Answer

Like the previous question that you answered

kc_kennylau · Answer

I just want to be fluent in this topic

kc_kennylau · Answer

(excuse me for my grammar mistakes of any kind, coz my brain ain't functioning properly now)

anonymous · Answer

Try this
mlar masses of C6H12O6 and water are 180 and 18 respectively.Glucose : Water
is 2 : 3 according to their masses. find the mole fraction of glucose

anonymous · Answer

Actually I am not studing chemistry in English. So even I dont know some words

kc_kennylau · Answer

What language is your native language?

anonymous · Answer

You probably dont know

kc_kennylau · Answer

Say it :)

anonymous · Answer

Its Sinhala

kc_kennylau · Answer

180*2 : 18*3
= 10*2 : 1*3
= 20 : 3

kc_kennylau · Answer

you're right on that haha

kc_kennylau · Answer

Am I correct?

anonymous · Answer

I am asking mole fraction of glucose. It means no. of glucose moles/Total moles

kc_kennylau · Answer

Wait, something wrong...

kc_kennylau · Answer

20:23 correct? I don't feel like it....

anonymous · Answer

Its like this.
the ratio is given according to their masses.We should always try not take masses as variables.So we should convert masses into moles

kc_kennylau · Answer

So 2/180 : (2/180 + 3/18) ?

anonymous · Answer

C6H12O6 : H2O = 2 : 3 according to their masses
 By converting to moles  = 2/180 : 3/18

anonymous · Answer

n=m/M

kc_kennylau · Answer

So I'm correct?

anonymous · Answer

2/180 : 3/18 
NOT
2/180 : (2/180 + 3/18)

anonymous · Answer

masses should be divided by molar masses

anonymous · Answer

In glucose its 2/180 and in water its 3/18

kc_kennylau · Answer

But you say total moles...

anonymous · Answer

Now we have found glucose and water moles
So glucose mole fraction is
2/180/ (2/180 + 3/18)

kc_kennylau · Answer

Oh, I see

anonymous · Answer

answer is 0.0625

kc_kennylau · Answer

Thanks!

anonymous · Answer

Hey current time in here is 10.22 PM. so i should probably go. I'll give u some more questions tommorrow

anonymous · Answer

Is that okay?

kc_kennylau · Answer

Okay, it's 0:55 for me now so I'll have to sleep anyways, see you :D

anonymous · Answer

Bye