NH3 has a solubility of 60g at 180C in 100.0mLof water.

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NH3 has a solubility of 60g at 180C in 100.0mLof
water.
HCl has a solubility of 60g at 480C in 100.0mLof
water.
KNO3 has a solubility of 60g at 380C in 100.0mLof
water.
KClO3 has a solubility of 60g at 100oC in 100.0g
water.
NH4Cl has a solubility of 60g at 66oC in 100.0g
water.
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NH3 has a solubility of 60g at 180C in 100.0mLof
water.
HCl has a solubility of 60g at 480C in 100.0mLof
water.
KNO3 has a solubility of 60g at 380C in 100.0mLof
water.
KClO3 has a solubility of 60g at 100oC in 100.0g
water.
NH4Cl has a solubility of 60g at 66oC in 100.0g
water.
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As you see from the graph the solubility of
NaNO3 INCREASES as temperature INCREASES. This is
due to the fact that the dissolving of this salt
is ENDOTHERMIC, energy absorbing, q is .
The solubility of NaNO3 at 520C is 120g in 100mL
of water.
The solubility of NaNO3 at 27oC is about 94g in
100mL of water.
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The solubility of NH3 DECREASES as the
temperature INCREASES, Therefore the dissolving
of ammonia is EXOTHERMIC it cannot give off
heat at higher temperatures which hinders
dissolving. The heat transfer is negative (-q)
for this reaction. This is typical of gasses
which dissolve poorly at higher temps.
At 10oC NH3 has a solubility of 70 grams of NH3
in 100 grams of water.
At 70oC NH3 has a solubility of 19 grams of NH3
in 100 grams of water.
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U DO IT NOW1/29/07

• What will occur if NaNO3 is cooled from 52oC to
  27oC?
• Which is the most soluble substance at 37oC,
  which is the least soluble.
• Identify the gases in the table.
• 4. What will occur as the temp. of NH3(aq) in
  solution is increased from 10oC to 70oC?

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The solubility of NaNO3 at 520C HOLDS 120g in
100mL of water.
As the temperature drops from 52oC to 27oC the
solubility drops from 120g to 94g. The difference
of 26g will precipitate out as a solid on the
bottom of the vessel. The 120g that is saturated
at 52oC is supersaturated at 27oC. At 27oC only
94 g can dissolve, 26g of the 120g must
precipitate to reach 94g. (520C,120g) (270C, 94g)
The solubility of NaNO3 at 27oC HOLDS about 94g
in 100mL of water.
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Energy is needed to break the electrostatic
attractions of the lattice, (lattice energy)
COOLING CAUSES
At 52oC 120g of NaNO3 will dissolve, the
solution has 120g in 100g water.
The electrostatic attractions to begin to form
the ionic crystal lattice.
COOLING
A precipitate forms.
The solution that could carry 120g at 52oC cannot
hold that much at lower tamps precipitate will
form as it cools.