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Chemistry P52 GT

Whats going to be the threshold of Chem P52 - no discussion atm

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rockpapers

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1) NH3 more soluble in water due to hydrogen bonding with water. Trichoromethane is an organic solvent so no hydrogen bonding.
2) Kpc= [NH3] trichoromethane/ [NH3] water and Kpc will be less than 1 since more soluble in water
3) Volumes do not need to be the same since only concentrations are used in Kpc and that will take in to account any changes in volume so it is not important to have same volume
4) 2NH3 + H2SO4 --> (NH4)2SO4
5) You can use any volume of sulphuric acid between 24-26, so i chose 25 cm3. Concentration of sulphuric acid was 0.500. Use formula n=c*v. You will get 0.0125 moles. NH3 moles will then be 0.0125*2=0.025 moles. then use n=c*v so 0.025=c*(25/1000) to get concentration of NH3 as 1 mole dm-3. Now to find out dilution factor you use the equation c1v1=c2v2 which is 5*x=1*(25/1000) so this will give x as 0.005 dm3 because we need to find out how much volume of the 5moldm-3 we are given is needed to form 1moldm-3 with volume of 25cm3. So since we have NH3 available as 5mole per dm3 and we need 0.005dm3 of it the dilution factor we get is 1/0.005= 200
6) To make up the concentration to 250cm3 use volumetric flask. Make up to the mark using the distilled water provided.
7) Safety was to use mask since trichloromethane was an anaesthetic and NH3 caused respiratory problems due to inhalation.
8) Indicator used methyl orange since weak base used against strong acid.
9) NH3 in water is more useful in titration because the trichloromethane can affect the titre value obtained by using sulphuric acid. Water is distilled and pure solvent so no effect.
9) After concordant titres were obtained, concentration of NH3 in water was found in 1 dm3. Then the original concentration of NH3 in water was found. The difference between the two values will be the concentration of NH3 in tricholoromethane. Divide both concentrations obtained to find Kpc using the equation given before.

1) The graph was a curve with 1 anomalous point, Make sure all points are plotted.
2) The anomalous point was on the right of the curve. The point was anomalous because this concentration of NO should have been present at a lower time measured. This means that wrong time recorded with stopwatch
3) Order of NO was 1 and use half life which was 100s and remained constant. You cannot use gradient to caluclate rate at each point since they expected you to draw construction lines and figure out and NOT by finding gradient.
4) Initial rate was negative something since NO concentration was decreasing
5) k calculated using initial rate and concentrations. unit was molecules cm3 s-1
6) converting to mol dm3 using avogadro number and converting cm3 to dm3
7) O3 present in excess so it is not limiting when NO concentration is measured to find the order.

Hope this helps!!! :)
 
T

TANJIAHOU

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92
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rockpapers said:
1) NH3 more soluble in water due to hydrogen bonding with water. Trichoromethane is an organic solvent so no hydrogen bonding.
2) Kpc= [NH3] trichoromethane/ [NH3] water and Kpc will be less than 1 since more soluble in water
3) Volumes do not need to be the same since only concentrations are used in Kpc and that will take in to account any changes in volume so it is not important to have same volume
4) 2NH3 + H2SO4 --> (NH4)2SO4
5) You can use any volume of sulphuric acid between 24-26, so i chose 25 cm3. Concentration of sulphuric acid was 0.500. Use formula n=c*v. You will get 0.0125 moles. NH3 moles will then be 0.0125*2=0.025 moles. then use n=c*v so 0.025=c*(25/1000) to get concentration of NH3 as 1 mole dm-3. Now to find out dilution factor you use the equation c1v1=c2v2 which is 5*x=1*(25/1000) so this will give x as 0.005 dm3 because we need to find out how much volume of the 5moldm-3 we are given is needed to form 1moldm-3 with volume of 25cm3. So since we have NH3 available as 5mole per dm3 and we need 0.005dm3 of it the dilution factor we get is 1/0.005= 200
6) To make up the concentration to 250cm3 use volumetric flask. Make up to the mark using the distilled water provided.
7) Safety was to use mask since trichloromethane was an anaesthetic and NH3 caused respiratory problems due to inhalation.
8) Indicator used methyl orange since weak base used against strong acid.
9) NH3 in water is more useful in titration because the trichloromethane can affect the titre value obtained by using sulphuric acid. Water is distilled and pure solvent so no effect.
9) After concordant titres were obtained, concentration of NH3 in water was found in 1 dm3. Then the original concentration of NH3 in water was found. The difference between the two values will be the concentration of NH3 in tricholoromethane. Divide both concentrations obtained to find Kpc using the equation given before.

1) The graph was a curve with 1 anomalous point, Make sure all points are plotted.
2) The anomalous point was on the right of the curve. The point was anomalous because this concentration of NO should have been present at a lower time measured. This means that wrong time recorded with stopwatch
3) Order of NO was 1 and use half life which was 100s and remained constant. You cannot use gradient to caluclate rate at each point since they expected you to draw construction lines and figure out and NOT by finding gradient.
4) Initial rate was negative something since NO concentration was decreasing
5) k calculated using initial rate and concentrations. unit was molecules cm3 s-1
6) converting to mol dm3 using avogadro number and converting cm3 to dm3
7) O3 present in excess so it is not limiting when NO concentration is measured to find the order.

Hope this helps!!! :)
Click to expand...
Your rate of reaction is not negative... Its always positive dude...
 
M

Muhammad Haris Ghani

Messages
238
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rockpapers said:
1) NH3 more soluble in water due to hydrogen bonding with water. Trichoromethane is an organic solvent so no hydrogen bonding.
2) Kpc= [NH3] trichoromethane/ [NH3] water and Kpc will be less than 1 since more soluble in water
3) Volumes do not need to be the same since only concentrations are used in Kpc and that will take in to account any changes in volume so it is not important to have same volume
4) 2NH3 + H2SO4 --> (NH4)2SO4
5) You can use any volume of sulphuric acid between 24-26, so i chose 25 cm3. Concentration of sulphuric acid was 0.500. Use formula n=c*v. You will get 0.0125 moles. NH3 moles will then be 0.0125*2=0.025 moles. then use n=c*v so 0.025=c*(25/1000) to get concentration of NH3 as 1 mole dm-3. Now to find out dilution factor you use the equation c1v1=c2v2 which is 5*x=1*(25/1000) so this will give x as 0.005 dm3 because we need to find out how much volume of the 5moldm-3 we are given is needed to form 1moldm-3 with volume of 25cm3. So since we have NH3 available as 5mole per dm3 and we need 0.005dm3 of it the dilution factor we get is 1/0.005= 200
6) To make up the concentration to 250cm3 use volumetric flask. Make up to the mark using the distilled water provided.
7) Safety was to use mask since trichloromethane was an anaesthetic and NH3 caused respiratory problems due to inhalation.
8) Indicator used methyl orange since weak base used against strong acid.
9) NH3 in water is more useful in titration because the trichloromethane can affect the titre value obtained by using sulphuric acid. Water is distilled and pure solvent so no effect.
9) After concordant titres were obtained, concentration of NH3 in water was found in 1 dm3. Then the original concentration of NH3 in water was found. The difference between the two values will be the concentration of NH3 in tricholoromethane. Divide both concentrations obtained to find Kpc using the equation given before.

1) The graph was a curve with 1 anomalous point, Make sure all points are plotted.
2) The anomalous point was on the right of the curve. The point was anomalous because this concentration of NO should have been present at a lower time measured. This means that wrong time recorded with stopwatch
3) Order of NO was 1 and use half life which was 100s and remained constant. You cannot use gradient to caluclate rate at each point since they expected you to draw construction lines and figure out and NOT by finding gradient.
4) Initial rate was negative something since NO concentration was decreasing
5) k calculated using initial rate and concentrations. unit was molecules cm3 s-1
6) converting to mol dm3 using avogadro number and converting cm3 to dm3
7) O3 present in excess so it is not limiting when NO concentration is measured to find the order.

Hope this helps!!! :)
Click to expand...
great thankyou almost the same answers but while naming the indicator you will have to give the range so that you may may clear for why you chose the particular indicator
 
M

Muhammad Haris Ghani

Messages
238
Reaction score
193
Points
53
rockpapers said:
1) NH3 more soluble in water due to hydrogen bonding with water. Trichoromethane is an organic solvent so no hydrogen bonding.
2) Kpc= [NH3] trichoromethane/ [NH3] water and Kpc will be less than 1 since more soluble in water
3) Volumes do not need to be the same since only concentrations are used in Kpc and that will take in to account any changes in volume so it is not important to have same volume
4) 2NH3 + H2SO4 --> (NH4)2SO4
5) You can use any volume of sulphuric acid between 24-26, so i chose 25 cm3. Concentration of sulphuric acid was 0.500. Use formula n=c*v. You will get 0.0125 moles. NH3 moles will then be 0.0125*2=0.025 moles. then use n=c*v so 0.025=c*(25/1000) to get concentration of NH3 as 1 mole dm-3. Now to find out dilution factor you use the equation c1v1=c2v2 which is 5*x=1*(25/1000) so this will give x as 0.005 dm3 because we need to find out how much volume of the 5moldm-3 we are given is needed to form 1moldm-3 with volume of 25cm3. So since we have NH3 available as 5mole per dm3 and we need 0.005dm3 of it the dilution factor we get is 1/0.005= 200
6) To make up the concentration to 250cm3 use volumetric flask. Make up to the mark using the distilled water provided.
7) Safety was to use mask since trichloromethane was an anaesthetic and NH3 caused respiratory problems due to inhalation.
8) Indicator used methyl orange since weak base used against strong acid.
9) NH3 in water is more useful in titration because the trichloromethane can affect the titre value obtained by using sulphuric acid. Water is distilled and pure solvent so no effect.
9) After concordant titres were obtained, concentration of NH3 in water was found in 1 dm3. Then the original concentration of NH3 in water was found. The difference between the two values will be the concentration of NH3 in tricholoromethane. Divide both concentrations obtained to find Kpc using the equation given before.

1) The graph was a curve with 1 anomalous point, Make sure all points are plotted.
2) The anomalous point was on the right of the curve. The point was anomalous because this concentration of NO should have been present at a lower time measured. This means that wrong time recorded with stopwatch
3) Order of NO was 1 and use half life which was 100s and remained constant. You cannot use gradient to caluclate rate at each point since they expected you to draw construction lines and figure out and NOT by finding gradient.
4) Initial rate was negative something since NO concentration was decreasing
5) k calculated using initial rate and concentrations. unit was molecules cm3 s-1
6) converting to mol dm3 using avogadro number and converting cm3 to dm3
7) O3 present in excess so it is not limiting when NO concentration is measured to find the order.

Hope this helps!!! :)
Click to expand...
sorry the rate is always positive
 
T

TANJIAHOU

Messages
92
Reaction score
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Di
rockpapers said:
1) NH3 more soluble in water due to hydrogen bonding with water. Trichoromethane is an organic solvent so no hydrogen bonding.
2) Kpc= [NH3] trichoromethane/ [NH3] water and Kpc will be less than 1 since more soluble in water
3) Volumes do not need to be the same since only concentrations are used in Kpc and that will take in to account any changes in volume so it is not important to have same volume
4) 2NH3 + H2SO4 --> (NH4)2SO4
5) You can use any volume of sulphuric acid between 24-26, so i chose 25 cm3. Concentration of sulphuric acid was 0.500. Use formula n=c*v. You will get 0.0125 moles. NH3 moles will then be 0.0125*2=0.025 moles. then use n=c*v so 0.025=c*(25/1000) to get concentration of NH3 as 1 mole dm-3. Now to find out dilution factor you use the equation c1v1=c2v2 which is 5*x=1*(25/1000) so this will give x as 0.005 dm3 because we need to find out how much volume of the 5moldm-3 we are given is needed to form 1moldm-3 with volume of 25cm3. So since we have NH3 available as 5mole per dm3 and we need 0.005dm3 of it the dilution factor we get is 1/0.005= 200
6) To make up the concentration to 250cm3 use volumetric flask. Make up to the mark using the distilled water provided.
7) Safety was to use mask since trichloromethane was an anaesthetic and NH3 caused respiratory problems due to inhalation.
8) Indicator used methyl orange since weak base used against strong acid.
9) NH3 in water is more useful in titration because the trichloromethane can affect the titre value obtained by using sulphuric acid. Water is distilled and pure solvent so no effect.
9) After concordant titres were obtained, concentration of NH3 in water was found in 1 dm3. Then the original concentration of NH3 in water was found. The difference between the two values will be the concentration of NH3 in tricholoromethane. Divide both concentrations obtained to find Kpc using the equation given before.

1) The graph was a curve with 1 anomalous point, Make sure all points are plotted.
2) The anomalous point was on the right of the curve. The point was anomalous because this concentration of NO should have been present at a lower time measured. This means that wrong time recorded with stopwatch
3) Order of NO was 1 and use half life which was 100s and remained constant. You cannot use gradient to caluclate rate at each point since they expected you to draw construction lines and figure out and NOT by finding gradient.
4) Initial rate was negative something since NO concentration was decreasing
5) k calculated using initial rate and concentrations. unit was molecules cm3 s-1
6) converting to mol dm3 using avogadro number and converting cm3 to dm3
7) O3 present in excess so it is not limiting when NO concentration is measured to find the order.

Hope this helps!!! :)
Click to expand...
Dilution factor 200?? If it is 200, your final solution will have a concentration of 5/200 = 0.025moldm-3. You don't use that formula c1v1 = c2v2 here. Original solution is 5moldm-3. A volume of it is to be diluted to get 1moldm-3. So dilution factor is 5 or 1/5.
 
Last edited:
talha196

talha196

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my partition coeff was greater than 1 since i wrote conc of nh3 in water/ conc of ammonia in trichloro
and for the reason why titration wasnt done using trichloromethane, i wrote just because conc of nh3 is too low in it very little vol of h2s04 will titrate with it giving more percentage error.
 
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