Molarity Problems Part Deux

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1) 2.3 moles of sodium chloride in 0.45 liters of water.

(2.3 moles) / (.45 liters)  =  5.1 moles/liter


2) 1.2 moles of calcium carbonate in 1.22 liters of water.

(1.2 moles) / (1.22 liters) = .984 moles/liter


3) 0.09 moles of sodium sulfate in 12 mL of water.

(0.09 moles) / (.012 liters) = 7.5 moles/liter


4) 0.75 moles of lithium fluoride in 65 mL of water.

 (.75 moles) / (.064 liters) = 11.7 moles/liter


5) 0.8 moles of magnesium acetate in 5 liters of water.

(.8 moles) / (5 liters) = .16 moles/liter


6) 120 grams of calcium nitrite in 240 mL of water.


7) 98 grams of sodium hydroxide in 2.2 liters of water.
8) 1.2 grams of hydrochloric acid in 25 mL of water.
9) 45 grams of ammonia in 0.75 L of water.

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Explain how you would make the following solutions. You should tell how many
grams of the substance you need to make the solution, not how many moles.

10) 2 L of 6 M HCl

Railroad Tracks:

6.0 moles HCl 36.45 g HCl 2 liters
1 liter
1 mole HCl

= 437.4 grams HCl (ack sig figs are messed up here...)

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11) 1.5 L of 2 M NaOH

Railroad tracks

2 moles NaOH 40.00 g NaOH 1.5 liters
1 liter
1 mole NaOH

=120 grams NaOH

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12) 0.75 L of 0.25 M Na2SO4

.25 moles Na2SO4 142.1 g Na2SO4 .75 liters
1 liter
1 mole Na2SO4

= 26.64 grams of Na2SO4

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13) 45 mL of 0.12 M sodium carbonate

.12 moles Na(CO3) 83.00 g Na(CO3) 1 liter 45 ml
1 liter
1 mole Na(CO3)
1000 ml

=.4482 grams of Na(CO3)

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14) 250 mL of 0.75 M lithium nitrite

.75 moles Li(NO2) 36.95 g Li(NO2) 1 liter 250 ml
1 liter
1 mole Li(NO2)
1000 ml
 

= 6.93 grams Li(NO2)


15) 56 mL of 1.1 M iron (II) phosphate
16) 6.7 L of 4.5 M ammonium nitrate
17) 4.5 mL of 0.05 M magnesium sulfate
18) 90 mL of 1.2 M BF3