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1. A 10ml solution contains 1g of NaCl (a)Find the molarity of Chlorine ions in this...

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lineekela | Student, Undergraduate | (Level 1) eNoter

Posted August 21, 2012 at 11:18 PM via web

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1. A 10ml solution contains 1g of NaCl (a)Find the molarity of Chlorine ions in this solution?

 

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jeew-m | College Teacher | (Level 1) Educator Emeritus

Posted August 22, 2012 at 1:22 AM (Answer #1)

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Molarity means the number of moles dissolved in one litre of solution.

 

Molar mass

Na = 23 g/mol

Cl = 35 g/mol

 

NaCl molar mass = 11+17 = 58 g/mol

 

Moles present in the solution = 1g/58g/mol

                                          = 0.017mol

 

0.017 moles are in 10ml. Molarity means the number of moles in 1000ml or 1 lire.

 

So molarity of NaCl = 0.017/10*1000

                            = 1.7 mol/lL

 

Molarity of NaCl is 1.7 mol/L

Sources:

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kavya--kammana | Student, Grade 12 | (Level 1) Valedictorian

Posted August 23, 2012 at 2:32 PM (Answer #2)

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1g of Nacl   (  = na= 23 & cl=35.5)( 23+35.5= 58.5)

WELL , NICE QUESTION .... WE HAVE MOLE CONCEPT AS A CHAPTER IN CHEMISTRY

 

No. of moles = given mass / molecular mass

                  =  1/ 58.5

                  =  0.017mole

 1Molar solution is a solution having 1mole of solute and 1 litre of solvent

       1 L = 1000 ml 

       x L  = 10 ml

     x =  10 *  1/ 1000 = 0.01 L 

 MOLARITY = 0.017 / 0.01 = 1.7 M

 

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sanjeetmanna | College Teacher | (Level 3) Assistant Educator

Posted August 23, 2012 at 10:05 PM (Answer #3)

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First we need a balanced chemical reaction which shows the dissociation of NaCl into its ions...

`NaCl -> (Na^+) + (Cl^-)`

Which means one mole of NaCl will produce only one mole of Cl- ions.

Given

1 g of NaCl.

Moles = mass/molar mass

Moles = `1/58.44`

Moles = 0.0171 of NaCl

Which means 1 g of NaCl will produce 0.0171 moles of `Cl^-` .

Molarity = moles/volume in litres.

Molarity = `0.0171/0.01`

Molarity = 1.71 M

Therefore 10 ml of solution containing 1 g of NaCl will 1.71 Molarity of `Cl^-` ions.

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