Question

a solution is prepared by adding 2 g of a substance in water . calculate the given solution.

Answer 1

Again water..???

Answer 2

yeah :P

Answer 3

teach me molarity , molality and all ities in this chapter .. please !

Answer 4

Oh My God..

Simply Kill me...

Answer 5

with ? .. knife or gun ? your wish :P

Answer 6

now your eyes do water i guess :P

Answer 7

Kill Water with Water if you can..

Answer 8

before 12:30 i want to finish this ... and start with biology .. you know biology water ?

Answer 9

water with water ? :P

Answer 10

No. I don't know..

In 11th grade I had not taken Biology as my Subject...

Answer 11

Yes water with water ..

Answer 12

and i dont want you to die .. because i like you and who do you think will teach me then .. ? :P

Answer 13

oh :(

Answer 14

@waterineyes there .. please ?

Answer 15

Is your question right ???

Answer 16

yes i guess !

Answer 17

Calculate the given solution ???

And you are not sure ?? guessing ???

Answer 18

okay .. it is right !

Answer 19

yeah water is the soln

Answer 20

By calculate the given solution what does that mean??

Answer 21

I am not understanding it properly..

Answer 22

you want the note book answer ?

Answer 23

what is Wb and Wa ?

Answer 24

Yes if you want to give then..

Are we here to calculate molarity molality mass percentage etc and etc like things ??

Answer 25

yeah !

Answer 26

Then tell me in simple language then.

making me confuse..

Answer 27

ha ha ha ha..

I want to laugh loudly..

Ha ha ha ha ha...

Answer 28

and why .. ?

Answer 29

may i know if you intake laughing gas instead of oxygen .. because for the past 3 days you've been laughing a hell lot :P

Answer 30

@Omniscience are you getting ashna question ??

Answer 31

is the formula c= n/v ? where you have to calculate the molarity..
my chemistry is about rusty

Answer 32

Molarity = moles/Litres

Answer 33

I dont know how you can calculate the concentration of something when you are not given a volume

Answer 34

For Molarity it is :

Number of moles of Solute dissolved per Litre of the Solution...

Answer 35

then you have to calculate the concentation of the solution>

Answer 36

I guess your answer would be

(2g/Molecular Mass of Compound)/(Volume of water)

Answer 37

How can we convert that 2g into number of moles and substance is also not given that what is it ...???

Any idea ??

Answer 38

This would be the only answer since nothing is given
(2g/Molecular Mass of Compound)/(Volume of water)

Answer 39

for compound identity or volume thus you can outline how to solve said problem if such things were given that would be the only possible answer you can give for such a question

Answer 40

In denominator it will be Volume of Water or Volume of whole Solution ???

Answer 41

remember

Moles = Grams/Molecular Mass

Answer 42

Since all we know is grams we can only state the moles of the compound as

( 2g/molecular mass )

then we sub that into the Molarity Formula

(2g/Molecular mass)/Litres of water

Answer 43

Ok but in case of Molarity in denominator we have 1 Litre of the Solution and not solvent only..

Answer 44

I guess I should write

(2g/Molecular mass)/Volume of solution

Answer 45

to correct for displacement

Answer 46

usually when you make a solution you use volumetric glassware so I forget about displacement

Answer 47

Yep this looks good to me...

Answer 48

the only time you really dont take displacement into account and only calculate the volume of solvent is when dealing with Molality

Answer 49

Yes..

In case of Mololity, it is number of moles of solute dissolved per KG of the solvent..

And remember here Mass includes and not Volume in the denominator..

Answer 50

*Molality...

Answer 51

I need to start visiting chemistry more often I miss solution questions

Answer 52

And I had studied these 5 years ago in 2007..

I am not used to study chemistry for last 4 years..
So I have no grip on it now...

Answer 53

Yeah I dont get to do this stuff in a lab anymore, due to being in university :S

Answer 54

what is going on ?

Answer 55

Looking cute @ashna

Answer 56

lol .. good morning .. i dont understand anything :/

Answer 57

first of all what is molarity ?
second of all what is molality ?

Answer 58

I am wondering I have been teaching a \(\frak{\underline{Cute \; \; Cat }}\) for last three days..

Answer 59

Molarity is a ratio of Moles in Volume of Solution

Answer 60

I write down the formula for you @ashna

Answer 61

The volume being in the unit litres

Answer 62

yea .. yu've been my teacher who makes me understand everything .. and it'd be complete if you could finish of this one too WATER :D

Answer 63

so if you had a 1M solution you have

1Mol/Per liter of solution

Answer 64

okay

Answer 65

We already came to a solution

Answer 66

Molarity:
(2g/Molecular mass)/Volume of solution

Answer 67

Molarity :

Molarity is defined as the Number of Moles of Solute dissolved per Litre of the Solution..

Do you know what Solute, Solvent and Solution are ???


So formula for Molarity is :

\[Molarity = \frac{Number \; Of \; Moles \; Of \; Solute}{Volume\; Of \; Solution}\]

Answer 68

The question doesn't ask for any particular type of solution you could make it a percent solution or g/mL

Answer 69

I would just go

2g/mL of solution

Answer 70

easiest answer is best answer

Answer 71

yeah i know solvent and solute ..what is solution ?

Answer 72

solution is what you get when you mix a solute with a solvent

Answer 73

Solution is formed when two substances are added one of them being in aqueous (liquid) form..

Solute is the quantity present in smaller amount in the solution..

Solvent is quantity present in greater amount..

Answer 74

yes but a solution is not a solution unless the two compounds can mix evenly

Answer 75

okay

Answer 76

but waterineyes has it right

Answer 77

Weight of Solute is denoted by : \(W_A\)

Weight of Solvent is denoted by : \(W_B\)

A represents Solute and B represents Solvent..

Answer 78

okay

Answer 79

What else @ashna ?/

Sorry we are left with Molality now..

See its definition properly there are two differences in Molality from Molarity..

Answer 80

what diff ?

Answer 81

Molality is mostly used when dealing with solutions that are hotter than room temperature

Answer 82

or low temperatures I assume as well, because volume of water can increase and decrease

Answer 83

Molality :

it is defined as Number of moles of Solute dissolved per kg (kilogram) of the solvent :

\[Molality = \frac{Number \; Of \; Moles \; Of \; Solute}{KG\; Of \; Solvent}\]

Can you find out ??

Answer 84

well liquids in general can change volume depending on temperature, thus we weight the solvent before hand so we have a set concentration

Answer 85

that doesnt change with temperature

Answer 86

@Australopithecus go slow..

Answer 87

find out what water ? the diff ?

Answer 88

Yes..

Answer 89

Just check the formulas for both and try to find out the difference ..

Answer 90

okay .. for molarity it is the volume of solvent and for molality it is the weight of the solvent .. ?

Answer 91

No no ...

Answer 92

?

Answer 93

The difference between molarity and molality

molarity is based on liters of total solution

Molality is based on Mass (which is constant with temperature) of the solvent by itself

We use molality when dealing with solutions that are not at normal temperature because volume increases and decreases depending on temperature, Mass is constant at all temperatures.

Answer 94

For Molarity it is Volume of Solution and not solvent..

Volume of Solution means : Volume of solvent + Volume of solute...

Answer 95

oh okay

Answer 96

@Australopithecus i said you are going faster than the speed of ashna...

Answer 97

See ashna:

First difference is : Clearly you can see there is Volume in Molarity and there is kg that is Mass in Molality..

Right ??