Date | May 2019 | Marks available | 1 | Reference code | 19M.1.hl.TZ2.3 |
Level | HL | Paper | 1 | Time zone | TZ2 |
Command term | Question number | 3 | Adapted from | N/A |
Question
What is the volume of gas when the pressure on 100 cm3 of gas is changed from 400 kPa to 200 kPa at constant temperature?
A. 50.0 cm3
B. 100 cm3
C. 200 cm3
D. 800 cm3
Markscheme
C
Examiners report
85 % of the candidates were able to deduce the new volume of a sample of gas after the pressure was halved. The most commonly chosen distractor was the value that assumed a direct proportionality between volume and pressure.
Syllabus sections
- 18M.1.sl.TZ1.3: Which graph shows the relationship between the volume and pressure of a fixed mass of an...
-
18M.2.sl.TZ2.1a:
Calculate the amount, in mol, of H2SO4.
-
17M.1.sl.TZ2.3:
What is the maximum volume, in dm3, of CO2(g) produced when 1.00 g of CaCO3(s) reacts with 20.0 cm3 of 2.00 moldm–3 HCl(aq)?
CaCO3(s) + 2HCl(aq) → CaCl2(aq) + H2O(l) + CO2(g)
Molar volume of gas = 22.7 dm3mol–1; Mr(CaCO3) = 100.00
A.
B.
C.
D.
-
17M.3.sl.TZ1.3:
Suggest how the end point of the titration might be estimated from the graph.
- 22M.1.sl.TZ2.1: What is the concentration of chloride ions, in mol dm−3, in a solution formed by mixing...
- 22M.1.sl.TZ2.3: Which graph represents the relationship between the amount of gas, n, and the absolute...
-
18M.2.sl.TZ2.1f:
Calculate the percentage by mass of magnesium hydroxide in the 1.24 g antacid tablet to three significant figures.
-
22M.1.sl.TZ1.2:
Which sample contains the fewest moles of HCl?
NA = 6.02 × 1023 mol–1.
Molar volume of an ideal gas at STP = 22.7 dm3 mol–1.
A. 10.0 cm3 of 0.1 mol dm–3 HCl (aq)B. 6.02 × 1024 molecules of HCl (g)
C. 0.365 g of HCl (g)
D. 2.27 dm3 of HCl (g) at STP
-
19M.2.hl.TZ1.3i:
Outline why a real gas differs from ideal behaviour at low temperature and high pressure.
-
18M.1.sl.TZ2.3:
What is the volume, in cm3, of the final solution if 100 cm3 of a solution containing 1.42 g of sodium sulfate, Na2SO4, is diluted to the concentration of 0.020 mol dm–3?
Mr(Na2SO4) = 142
A. 50
B. 400
C. 500
D. 600
-
17M.2.sl.TZ2.2b.ii:
The sample of K2Cr2O7(s) in (i) was dissolved in distilled water to form 0.100 dm3 solution. Calculate its molar concentration.
-
17M.3.sl.TZ1.4:
State and explain how the graph would differ if 1 moldm−3 sulfuric acid had been used instead of 1 moldm−3 hydrochloric acid.
-
20N.2.sl.TZ0.1b(i):
Calculate the amount, in , of manganese(IV) oxide added.
- 18M.1.sl.TZ2.6: Which electron transition emits energy of the longest wavelength?
-
18M.2.sl.TZ2.1d:
Calculate the amount of H2SO4 that reacted with Mg(OH)2.
- 21N.1.sl.TZ0.4: The two containers shown are connected by a valve. What is the total pressure after the valve...
- 18N.1.sl.TZ0.2: The volume of a sample of gas measured at 27 °C is 10.0 dm3. What is the temperature when the...
-
18N.3.sl.TZ0.1f.ii:
Suggest why the end point of the titration is difficult to determine, even with the addition of starch to turn the remaining free iodine black.
-
17M.2.sl.TZ2.7b.ii:
Calculate the molar mass of the acid.
-
18N.3.sl.TZ0.1f.i:
Copper(II) ions are reduced to copper(I) iodide by the addition of potassium iodide solution, releasing iodine that can be titrated with sodium thiosulfate solution, Na2S2O3 (aq). Copper(I) iodide is a white solid.
4I− (aq) + 2Cu2+ (aq) → 2CuI (s) + I2 (aq)
I2 (aq) + 2S2O32− (aq) → 2I− (aq) + S4O62− (aq)
Deduce the overall equation for the two reactions by combining the two equations.
-
18N.2.hl.TZ0.1a.i:
Determine the limiting reactant showing your working.
-
19M.2.hl.TZ2.5d(iii):
100.0cm3 of soda water contains 3.0 × 10−2g NaHCO3.
Calculate the concentration of NaHCO3 in mol dm−3.
-
17M.2.sl.TZ1.4h.ii:
Calculate the volume, in dm3, of nitrogen formed under SATP conditions. (The volume of 1 mol of gas = 24.8 dm3 at SATP.)
-
19M.2.sl.TZ2.2c:
The experiment is repeated using the same amount of dinitrogen monoxide in the same apparatus, but at a lower temperature.
Sketch, on the axes in question 2, the graph that you would expect.
-
19M.1.sl.TZ2.4:
What is the concentration, in mol dm−3, of 20.0 g of NaOH (Mr = 40.0) in 500.0 cm3?
A. 0.250
B. 0.500
C. 1.00
D. 4.00
-
19M.2.sl.TZ2.5b(ii):
100.0 cm3 of soda water contains 3.0 × 10−2 g NaHCO3.
Calculate the concentration of NaHCO3 in mol dm−3.
-
17M.3.sl.TZ2.15a.i:
Calculate the amounts, in mol, of each reactant.
-
17M.3.sl.TZ2.15a.ii:
Calculate, in g, the theoretical yield of aspirin.
-
19M.2.hl.TZ2.2a:
Explain why, as the reaction proceeds, the pressure increases by the amount shown.
-
19M.1.sl.TZ2.3:
What is the volume of gas when the pressure on 100 cm3 of gas is changed from 400 kPa to 200 kPa at constant temperature?
A. 50.0 cm3
B. 100 cm3
C. 200 cm3
D. 800 cm3
-
19M.1.sl.TZ1.4:
Which graph would not show a linear relationship for a fixed mass of an ideal gas with all other variables constant?
A. P against V
B. P against
C. P against T
D. V against T
-
16N.1.sl.TZ0.4:
5.0mol of Fe2O3(s) and 6.0mol of CO(g) react according to the equation below. What is the limiting reactant and how many moles of the excess reactant remain unreacted?
Fe2O3(s) + 3CO(g) → 2Fe(s) + 3CO2(g)
-
18M.2.sl.TZ2.1c:
The excess sulfuric acid required 20.80 cm3 of 0.1133 mol dm−3 NaOH for neutralization.
Calculate the amount of excess acid present.
-
18M.2.sl.TZ1.1c:
Urea can be made by reacting potassium cyanate, KNCO, with ammonium chloride, NH4Cl.
KNCO(aq) + NH4Cl(aq) → (H2N)2CO(aq) + KCl(aq)
Determine the maximum mass of urea that could be formed from 50.0 cm3 of 0.100 mol dm−3 potassium cyanate solution.
-
16N.1.sl.TZ0.3:
The complete combustion of 15.0cm3 of a gaseous hydrocarbon X produces 60.0 cm3 of carbon dioxide gas and 75.0 cm3 of water vapour. What is the molecular formula of X? (All volumes are measured at the same temperature and pressure.)
A. C4H6
B. C4H8
C. C4H10
D. C6H10 -
18N.1.sl.TZ0.4:
An antacid tablet containing 0.50 g of NaHCO3 (Mr = 84) is dissolved in water to give a volume of 250 cm3. What is the concentration, in mol dm−3, of HCO3− in this solution?
A.
B.
C.
D.
-
19M.3.hl.TZ2.1c(ii):
A mean daily lead intake of greater than 5.0 × 10−6 g per kg of body weight results in increased lead levels in the body.
Calculate the volume, in dm3, of tap water from experiment 8 which would exceed this daily lead intake for an 80.0 kg man.
- 19N.2.sl.TZ0.2a(i): Determine the mole ratio of S2O32− to O2, using the balanced equations.
- 19N.2.sl.TZ0.6a(iv): Suggest why water vapour deviates significantly from ideal behaviour when the gases are...
- 19N.3.sl.TZ0.2a(i): Describe the effect of increasing the voltage on the chemical yield of: Ethanal using...
-
19N.2.sl.TZ0.6a(iii):
Calculate the pressure, in kPa, of this gas in a 10.0 dm3 air bag at 127°C, assuming no gas escapes.
-
19N.3.sl.TZ0.16d:
Calculate the pH of a buffer solution which contains 0.20 mol dm−3 ethanoic acid and 0.50 mol dm−3 sodium ethanoate. Use section 1 of the data booklet.
pKa (ethanoic acid) = 4.76
-
17M.1.sl.TZ1.3:
5.0 cm3 of 2.00 moldm–3 sodium carbonate solution, Na2CO3(aq), was added to a volumetric flask and the volume was made up to 500 cm3 with water. What is the concentration, in moldm–3, of the solution?
A. 0.0050
B. 0.0040
C. 0.020
D. 0.010
-
19M.1.hl.TZ1.2:
What volume of carbon dioxide, CO2 (g), can be obtained by reacting 1 dm3 of methane, CH4 (g), with 1 dm3 of oxygen, O2 (g)?
CH4 (g) + 2O2 (g) → CO2 (g) + 2H2O (l)
A. 0.5 dm3
B. 1 dm3
C. 2 dm3
D. 6 dm3
- 21M.1.sl.TZ1.2: What is the resulting concentration, in mol dm−3, when 1.0 cm3 of 0.500 mol dm−3 nitric...
-
18M.1.sl.TZ2.4:
What is the percentage yield when 2.0 g of ethene, C2H4, is formed from 5.0 g of ethanol, C2H5OH?
Mr(ethene) = 28; Mr(ethanol) = 46A.
B.
C.
D.
-
19M.2.hl.TZ2.2d:
The experiment is repeated using the same amount of dinitrogen monoxide in the same apparatus, but at a lower temperature.
Sketch, on the axes in question 2, the graph that you would expect.
-
17M.2.sl.TZ2.7b.i:
Calculate the amount, in mol, of NaOH(aq) used.
-
19N.2.sl.TZ0.2a(iii):
The day 5 sample contained 5.03 × 10−5 moles of oxygen.
Determine the 5-day biochemical oxygen demand of the pond, in mg dm−3 (“parts per million”, ppm).
-
18N.3.sl.TZ0.1c:
Outline how a solution of 0.0100 mol dm−3 is obtained from a standard 1.000 mol dm−3 copper(II) sulfate solution, including two essential pieces of glassware you would need.
-
19N.1.sl.TZ0.1:
0.10 mol of hydrochloric acid is mixed with 0.10 mol of calcium carbonate.
2HCl (aq) + CaCO3 (s) → CaCl2 (aq) + H2O (l) + CO2 (g)
Which is correct?
-
17N.1.hl.TZ0.3:
What is the pressure, in Pa, inside a 1.0 m3 cylinder containing 10 kg of H2 (g) at 25 ºC?
R = 8.31 J K–1 mol–1; pV = nRT
A.
B.
C.
D.
-
17M.1.sl.TZ2.4:
Which factors affect the molar volume of an ideal gas?
A. I and II only
B. I and III only
C. II and III only
D. I, II and III
-
18M.2.hl.TZ1.1c:
Urea can be made by reacting potassium cyanate, KNCO, with ammonium chloride, NH4Cl.
KNCO(aq) + NH4Cl(aq) → (H2N)2CO(aq) + KCl(aq)
Determine the maximum mass of urea that could be formed from 50.0 cm3 of 0.100 mol dm−3 potassium cyanate solution.
-
22M.2.sl.TZ2.1b(i):
Calculate the molar concentration of the resulting solution of lithium hydroxide.
-
22M.2.sl.TZ2.1b(ii):
Calculate the volume of hydrogen gas produced, in cm3, if the temperature was 22.5 °C and the pressure was 103 kPa. Use sections 1 and 2 of the data booklet.
-
18N.3.hl.TZ0.1g:
Titration is another method for analysing the solution obtained from adding brass to nitric acid.
Copper(II) ions are reduced to copper(I) iodide by the addition of potassium iodide solution, releasing iodine that can be titrated with sodium thiosulfate solution, Na2S2O3 (aq). Copper(I) iodide is a white solid.
4I− (aq) + 2Cu2+ (aq) → 2CuI (s) + I2 (aq)
I2 (aq) + 2S2O32− (aq) → 2I− (aq) + S4O62− (aq)
Suggest why the end point of the titration is difficult to determine, even with the addition of starch to turn the remaining free iodine black.
-
18N.2.hl.TZ0.1a.ii:
The mass of copper obtained experimentally was 0.872 g. Calculate the percentage yield of copper.
-
19N.3.hl.TZ0.8:
1.40 × 10−3 g of NaOH (s) are dissolved in 250.0 cm3 of 1.00 × 10−11 mol dm−3 Pb(OH)2 (aq) solution.
Determine the change in lead ion concentration in the solution, using section 32 of the data booklet.
-
17N.2.sl.TZ0.4b:
0.150 g sample of menthol, when vaporized, had a volume of 0.0337 dm3 at 150 °C and 100.2 kPa. Calculate its molar mass showing your working.
-
19N.2.hl.TZ0.6b:
Solid copper(II) chloride absorbs moisture from the atmosphere to form a hydrate of formula CuCl2•H2O.
A student heated a sample of hydrated copper(II) chloride, in order to determine the value of . The following results were obtained:
Mass of crucible = 16.221 g
Initial mass of crucible and hydrated copper(II) chloride = 18.360 g
Final mass of crucible and anhydrous copper(II) chloride = 17.917 gDetermine the value of .
-
19M.3.sl.TZ2.1c(ii):
A mean daily lead intake of greater than 5.0 × 10−6 g per kg of body weight results in increased lead levels in the body.
Calculate the volume, in dm3, of tap water from experiment 8 which would exceed this daily lead intake for an 80.0 kg man.
-
20N.2.hl.TZ0.1b(iii):
Determine the excess amount, in , of the other reactant.
-
18M.2.hl.TZ1.1g:
Calculate the maximum volume of CO2, in cm3, produced at STP by the combustion of 0.600 g of urea, using sections 2 and 6 of the data booklet.
-
17M.2.sl.TZ2.2b.iii:
10.0 cm3 of the waste sample required 13.24 cm3 of the K2Cr2O7 solution. Calculate the molar concentration of Sn2+(aq) in the waste sample.
- 21M.1.sl.TZ1.1: Which contains the most atoms of oxygen? A. 64 g of O2 B. 1.2 × 1024 molecules of O2...
- 21N.2.hl.TZ0.6c(ii): Deduce the mole ratio of O2 consumed in step I to S2O32− used in step III.
-
16N.2.hl.TZ0.2c:
5.00 g of an impure sample of hydrated ethanedioic acid, (COOH)2•2H2O, was dissolved in water to make 1.00 dm3 of solution. 25.0 cm3 samples of this solution were titrated against a 0.100 mol dm-3 solution of sodium hydroxide using a suitable indicator.
(COOH)2 (aq) + 2NaOH (aq) → (COONa)2 (aq) + 2H2O (l)
The mean value of the titre was 14.0 cm3.
(i) Suggest a suitable indicator for this titration. Use section 22 of the data booklet.
(ii) Calculate the amount, in mol, of NaOH in 14.0 cm3 of 0.100 mol dm-3 solution.
(iii) Calculate the amount, in mol, of ethanedioic acid in each 25.0 cm3 sample.
(iv) Determine the percentage purity of the hydrated ethanedioic acid sample.
-
21M.2.hl.TZ2.1d(i):
Determine the mass, in g, of CaCO3 (s) produced by reacting 2.41 dm3 of 2.33 × 10−2 mol dm−3 of Ca(OH)2 (aq) with 0.750 dm3 of CO2 (g) at STP.
-
16N.1.sl.TZ0.2:
Which volume, in cm3, of 0.20 mol dm-3 NaOH (aq) is needed to neutralize 0.050 mol of H2S(g)?
H2S(g) + 2NaOH(aq) → Na2S(aq) + 2H2O(l)
A. 0.25
B. 0.50
C. 250
D. 500 -
20N.2.hl.TZ0.1b(iv):
Calculate the volume of chlorine, in , produced if the reaction is conducted at standard temperature and pressure (STP). Use section 2 of the data booklet.
-
20N.3.hl.TZ0.11e(iii):
Suggest a wavenumber absorbed by methane gas.
-
21M.2.hl.TZ1.4c(ii):
8.00 g of methane is completely converted to methanol. Calculate, to three significant figures, the final volume of hydrogen at STP, in dm3. Use sections 2 and 6 of the data booklet.
-
21M.2.sl.TZ2.1a:
Calcium carbonate is heated to produce calcium oxide, CaO.
CaCO3 (s) → CaO (s) + CO2 (g)
Calculate the volume of carbon dioxide produced at STP when 555 g of calcium carbonate decomposes. Use sections 2 and 6 of the data booklet.
-
21M.1.sl.TZ2.1:
0.20 mol of magnesium is mixed with 0.10 mol of hydrochloric acid.
Which is correct?
- 21M.1.sl.TZ2.2: Which amount, in mol, of sodium chloride is needed to make 250 cm3 of 0.10 mol dm−3...
-
16N.2.sl.TZ0.2c:
5.00 g of an impure sample of hydrated ethanedioic acid, (COOH)2•2H2O, was dissolved in water to make 1.00 dm3 of solution. 25.0 cm3 samples of this solution were titrated against a 0.100 mol dm-3 solution of sodium hydroxide using a suitable indicator.
(COOH)2 (aq) + 2NaOH (aq) → (COONa)2 (aq) + 2H2O (l)
The mean value of the titre was 14.0 cm3.
(i) Calculate the amount, in mol, of NaOH in 14.0 cm3 of 0.100 mol dm-3 solution.
(ii) Calculate the amount, in mol, of ethanedioic acid in each 25.0 cm3 sample.
(iii) Determine the percentage purity of the hydrated ethanedioic acid sample.
-
21M.2.sl.TZ2.1e(ii):
2.85 g of CaCO3 was collected in the experiment in e(i). Calculate the percentage yield of CaCO3.
(If you did not obtain an answer to e(i), use 4.00 g, but this is not the correct value.)
-
19M.2.sl.TZ1.3b:
Sodium peroxide, Na2O2, is formed by the reaction of sodium oxide with oxygen.
2Na2O (s) + O2 (g) → 2Na2O2 (s)
Calculate the percentage yield of sodium peroxide if 5.00 g of sodium oxide produces 5.50 g of sodium peroxide.
-
16N.3.sl.TZ0.18a:
Determine the percentage experimental yield of the product after recrystallization. The molar masses are as follows: M(salicylic acid) = 138.13 g mol−1, M(aspirin) = 180.17 g mol−1. (You do not need to process the uncertainties in the calculation.)
-
18N.2.sl.TZ0.1a.ii:
The mass of copper obtained experimentally was 0.872 g. Calculate the percentage yield of copper.
-
20N.1.sl.TZ0.4:
Which volume of ethane gas, in , will produce of carbon dioxide gas when mixed with of oxygen gas, assuming the reaction goes to completion?
A.
B.
C.
D.
-
21M.2.sl.TZ1.2c:
A gaseous sample of nitrogen, contaminated only with hydrogen sulfide, was reacted with excess sodium hydroxide solution at constant temperature. The volume of the gas changed from 550 cm3 to 525 cm3.
Determine the mole percentage of hydrogen sulfide in the sample, stating one assumption you made.
-
18N.2.sl.TZ0.1a.i:
Determine the limiting reactant showing your working.
-
20N.2.sl.TZ0.1b(iv):
Calculate the volume of chlorine, in , produced if the reaction is conducted at standard temperature and pressure (STP). Use section 2 of the data booklet.
-
21M.2.sl.TZ2.1d(ii):
Determine the volume, in dm3, of 0.015 mol dm−3 calcium hydroxide solution needed to neutralize 35.0 cm3 of 0.025 mol dm−3 HCl (aq).
-
19M.2.sl.TZ2.2a:
Explain why, as the reaction proceeds, the pressure increases by the amount shown.
-
21M.2.hl.TZ2.1d(ii):
2.85 g of CaCO3 was collected in the experiment in d(i). Calculate the percentage yield of CaCO3.
(If you did not obtain an answer to d(i), use 4.00 g, but this is not the correct value.)
-
17M.2.sl.TZ1.4h.i:
Calculate, showing your working, the mass of hydrazine needed to remove all the dissolved oxygen from 1000 dm3 of the sample.
-
20N.2.sl.TZ0.1b(ii):
Determine the limiting reactant, showing your calculations.
-
18M.1.sl.TZ1.4:
What is the percentage yield when 7 g of ethene produces 6 g of ethanol?
Mr(ethene) = 28 and Mr(ethanol) = 46
C2H4(g) + H2O(g) → C2H5OH(g)
A.
B.
C.
D.
-
20N.2.sl.TZ0.1b(iii):
Determine the excess amount, in , of the other reactant.
-
17M.3.sl.TZ2.2b.ii:
Suggest one improvement to the investigation.
-
20N.2.hl.TZ0.1b(i):
Calculate the amount, in , of manganese(IV) oxide added.
-
20N.3.hl.TZ0.18a(i):
Calculate the mole fraction of ethanal in the mixture.
-
20N.3.hl.TZ0.12a:
Show that the mass of the 238U isotope in the rock is .
-
20N.3.hl.TZ0.18a(ii):
The vapour pressure of pure ethanal at is .
Calculate the vapour pressure of ethanal above the liquid mixture at .
-
20N.3.sl.TZ0.9f(iii):
Suggest a wavenumber absorbed by methane gas.
-
18N.3.hl.TZ0.1d:
Outline how a solution of 0.0100 mol dm−3 is obtained from a standard 1.000 mol dm−3 copper(II) sulfate solution, including two essential pieces of glassware you would need.
-
17N.2.sl.TZ0.1c:
Calculate the concentration of ethanoic acid, CH3COOH, in mol dm–3.
-
16N.2.sl.TZ0.3c:
The precipitate of sulfur makes the mixture cloudy, so a mark underneath the reaction mixture becomes invisible with time.
10.0 cm3 of 2.00 mol dm-3 hydrochloric acid was added to a 50.0 cm3 solution of sodium thiosulfate at temperature, T1. Students measured the time taken for the mark to be no longer visible to the naked eye. The experiment was repeated at different concentrations of sodium thiosulfate.
Show that the hydrochloric acid added to the flask in experiment 1 is in excess.
-
20N.3.sl.TZ0.10a:
Show that the mass of the isotope in the rock is .
-
21M.2.sl.TZ2.1e(i):
Determine the mass, in g, of CaCO3 (s) produced by reacting 2.41 dm3 of 2.33 × 10−2 mol dm−3 of Ca(OH)2 (aq) with 0.750 dm3 of CO2 (g) at STP.
-
17M.1.sl.TZ1.4:
What is the expression for the volume of hydrogen gas, in dm3, produced at STP when 0.30 g of magnesium reacts with excess hydrochloric acid solution?
Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)
Molar volume of an ideal gas at STP = 22.7 dm3mol−1
A.
B.
C.
D.
-
17M.3.sl.TZ2.2b.i:
Explain why this experiment might give a low result for the molar mass of butane.
-
21M.2.hl.TZ2.1a:
Calcium carbonate is heated to produce calcium oxide, CaO.
CaCO3 (s) → CaO (s) + CO2 (g)
Calculate the volume of carbon dioxide produced at STP when 555 g of calcium carbonate decomposes. Use sections 2 and 6 of the data booklet.
-
21M.2.hl.TZ2.1c(ii):
Determine the volume, in dm3, of 0.015 mol dm−3 calcium hydroxide solution needed to neutralize 35.0 cm3 of 0.025 mol dm−3 HCl (aq).
-
17N.2.hl.TZ0.2d.ii:
0.150 g sample of menthol, when vaporized, had a volume of 0.0337 dm3 at 150 °C and 100.2 kPa. Calculate its molar mass showing your working.
-
20N.2.hl.TZ0.1b(ii):
Determine the limiting reactant, showing your calculations.
-
19N.2.sl.TZ0.5b:
Solid copper(II) chloride absorbs moisture from the atmosphere to form a hydrate of formula CuCl2•H2O.
A student heated a sample of hydrated copper(II) chloride, in order to determine the value of . The following results were obtained:
Mass of crucible = 16.221 g
Initial mass of crucible and hydrated copper(II) chloride = 18.360 g
Final mass of crucible and anhydrous copper(II) chloride = 17.917 gDetermine the value of .
-
22M.2.hl.TZ1.1b(iii):
Assume the reaction in (a)(i) is the only one occurring and it goes to completion, but some product has been lost from the crucible. Deduce the percentage yield of magnesium oxide in the crucible.
-
22M.2.hl.TZ1.1c(i):
Evaluate whether this, rather than the loss of product, could explain the yield found in (b)(iii).
-
22M.2.hl.TZ1.4b:
Determine the concentration, in mol dm–3, of the solution formed when 900.0 dm3 of NH3 (g) at 300.0 K and 100.0 kPa, is dissolved in water to form 2.00 dm3 of solution. Use sections 1 and 2 of the data booklet.
-
19M.2.hl.TZ1.3f:
Sodium peroxide, Na2O2, is formed by the reaction of sodium oxide with oxygen.
2Na2O (s) + O2 (g) → 2Na2O2 (s)
Calculate the percentage yield of sodium peroxide if 5.00g of sodium oxide produces 5.50g of sodium peroxide.
-
22M.2.sl.TZ1.1b(iii):
Assume the reaction in (a)(i) is the only one occurring and it goes to completion, but some product has been lost from the crucible. Deduce the percentage yield of magnesium oxide in the crucible.
-
22M.2.sl.TZ1.1c(i):
Evaluate whether this, rather than the loss of product, could explain the yield found in (b)(iii).
-
22M.2.sl.TZ1.2e(ii):
Determine the concentration, in mol dm–3, of the solution formed when 900.0 dm3 of NH3 (g) at 300.0 K and 100.0 kPa, is dissolved in water to form 2.00 dm3 of solution. Use sections 1 and 2 of the data booklet.
-
21M.2.sl.TZ1.4c(ii):
8.00 g of methane is completely converted to methanol. Calculate, to three significant figures, the final volume of hydrogen at STP, in dm3. Use sections 2 and 6 of the data booklet.
-
21M.1.sl.TZ1.3:
What volume of oxygen, in dm3 at STP, is needed when 5.8 g of butane undergoes complete combustion?
A.
B.
C.
D.
-
21N.2.hl.TZ0.6c(i):
Calculate the amount, in moles of Na2S2O3 used in the titration.
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21N.2.sl.TZ0.6c(i):
Calculate the amount, in moles of Na2S2O3 used in the titration.
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21N.2.hl.TZ0.6c(iii):
Calculate the concentration of dissolved oxygen, in mol dm−3, in the sample.
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21N.2.sl.TZ0.6c(iii):
Calculate the concentration of dissolved oxygen, in mol dm−3, in the sample.
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21N.2.sl.TZ0.5c:
Calculate the concentration of H3PO4 if 25.00 cm3 is completely neutralised by the addition of 28.40 cm3 of 0.5000 mol dm−3 NaOH.
- 21N.2.sl.TZ0.6c(ii): Deduce the mole ratio of O2 consumed in step I to S2O32− used in step III.
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21N.2.hl.TZ0.5c:
Calculate the concentration of H3PO4 if 25.00 cm3 is completely neutralised by the addition of 28.40 cm3 of 0.5000 mol dm−3 NaOH.