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Topic: Determine the grams of Solute to prepare these solutions  (Read 6891 times)

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Offline TheCluelessOne

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Determine the grams of Solute to prepare these solutions
« on: February 08, 2013, 09:39:57 AM »
I guess we are supposed to find the Solute of the solution

0.289 liters of a 0.00300 M Cu(NO3)2 solution

16.00 mililiters of a 5.90-molar Pb(NO3)2 Solution

508 mL of a 2.75-molar NaF solution

6.20 L of a 3.76-molar Na2O solution

Offline Borek

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Re: Determine the grams of Solute to prepare these solutions
« Reply #1 on: February 08, 2013, 09:42:31 AM »
I guess you guess right.

There is a possible problem if the solution are to be prepared using hydrated salts.
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Offline TheCluelessOne

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Re: Determine the grams of Solute to prepare these solutions
« Reply #2 on: February 08, 2013, 09:49:39 AM »
I dont think we are using hydrated salts

Offline Borek

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Re: Determine the grams of Solute to prepare these solutions
« Reply #3 on: February 08, 2013, 09:59:28 AM »
So, how much solute in 0.289 liters of a 0.00300 M solution?
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Offline TheCluelessOne

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Re: Determine the grams of Solute to prepare these solutions
« Reply #4 on: February 08, 2013, 10:05:38 AM »
the solution i was taught was
M*Liter Solution*Molar Mass

so
0.163 grams of solute?

but the others are more complicated

Offline Borek

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Re: Determine the grams of Solute to prepare these solutions
« Reply #5 on: February 08, 2013, 10:09:51 AM »
OK so far.

There is nothing complicated in converting volume in mL to volume in L.
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Offline TheCluelessOne

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Re: Determine the grams of Solute to prepare these solutions
« Reply #6 on: February 08, 2013, 10:15:59 AM »
well I don't know much about these equations  ???   
                   :spindown:
how do you convert molar to M(molality)?

Offline Borek

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Re: Determine the grams of Solute to prepare these solutions
« Reply #7 on: February 08, 2013, 10:28:40 AM »
M is usually molarity and molar means exactly the same. No need for molality here.

How many mL in 1 L?
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Offline TheCluelessOne

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Re: Determine the grams of Solute to prepare these solutions
« Reply #8 on: February 08, 2013, 10:32:38 AM »
so there is no difference between M and molar?

That was the only part I was confused about :)

and 1000 mL in 1 L

so I just need to move a few decimal places..

Offline Borek

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Re: Determine the grams of Solute to prepare these solutions
« Reply #9 on: February 08, 2013, 11:29:57 AM »
Nothing more complicated here.
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Offline TheCluelessOne

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Re: Determine the grams of Solute to prepare these solutions
« Reply #10 on: February 08, 2013, 11:57:10 AM »
so number 2 would be

31.26 grams of solute...

and number 3 would be

58.660 Grams of Solute

and number 4

1444.878 g of solute

Am I right?

Offline Borek

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Re: Determine the grams of Solute to prepare these solutions
« Reply #11 on: February 08, 2013, 12:11:53 PM »
Your sigfigs are off, but apparently you got the idea.
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Offline TheCluelessOne

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Re: Determine the grams of Solute to prepare these solutions
« Reply #12 on: February 08, 2013, 12:29:14 PM »
So how do you go about Sigfigs?

make for example #2

16.00 mL of a 5.90 M Pb(NO3)2 Solution

when I convert 16.00 mL to L its 0.1600 mL and I know that 1 and 6 are sigfigs, do i have to include the 2 zero's too?

so it makes 4 sigfigs?


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