| This test consists of 40 questions, and should be completed in 1 hour. For each question there are four responses only one of which is correct. You should use your calculator and the Data Booklet. (Please note however that in the actual IB examination (Paper 1 - multiple choice), the use of a calculator is not permitted. Questions are formulated in such a manner so as not to require the use of a calculator). Similarly the use of the IB Data Booklet is not permitted, but a simplified Periodic Table with atomic numbers and relative atomic masses is provided). Marks will not be deducted for incorrect answers, so you should attempt all questions. E.P. Anthony October 1999
1. One mole of N2H4 molecules contains approximately:
2. Which one of the following contains the greatest mass of carbon ?
3. What is the approximate mass in grams of 1 nitrogen molecule N2 ?
4. Which one of the following contains the smallest number of molecules ?
5. The nitrogen compound which contains the largest mass percentage of nitrogen is ?
6. Which hydrocarbon would, on complete combustion in oxygen, produce CO2 and H2O in the mole ratio: 1.0 mol CO2 / 1.33 mol H2O
7. Which one of the following could represent an empirical formula ?
8. The number of grams of hydrogen in a sample of ethanoic acid C2H4O2 that contains 48.0 g of carbon is :
9. The sample which contains 3.01 x 1023 atoms is :
10. A compound contains 40.0% carbon, 6.7% hydrogen and 53.3% oxygen by mass. How many hydrogen atoms are there in the simplest formula of the compound ?
11. One molecule of a compound contains 12 atoms of carbon. The mass percentage of carbon in the compound is 42.1%. What is the relative molecular mass (Mr) of the compound ?
12. A certain compound has a relative molecular mass (Mr) of 60. All of the following are possible simplest formulae for this compound EXCEPT
13. Caffeine (Mr = 194) contains 28.9% of nitrogen by mass. The number of nitrogen atoms in a caffeine molecule is
14. When 32 g of CH4 are reacted with 32 g of O2 according to the equation:
All of the following statements are true except:
D. the total mass of CO2 and H2O produced will be 64 g.
15.
How many moles of water will be produced if 100 g of potassium hydrogen carbonate are completely decomposed by heat ?
16. How many grams of AgCl would be precipitated if an excess of AgNO3 solution were added to 250.0 cm3 of 0.500 mol dm-3 KCl solution ?
17. If 100.00 cm3 of a NaOH solution are required for the neutralization of a 25.00 cm3 sample of 0.1000 mol dm-3 H2SO4, what is the concentration of the NaOH ?
18. The Avogadro constant (L) corresponds to
19. The volume of 0.250 mol dm-3 nitric acid, HNO3, required to react with 5.80 g of magnesium hydroxide, Mg(OH)2, according to the following equation is 2HNO3 + Mg(OH)2 ------> Mg(NO3)2 + 2H2O
20. A 27.0 g sample of an unknown carbon-hydrogen compound was burned in excess oxygen to form 88.0 g of CO2 and 27.0 g of H2O. What is a possible molecular formula of the hydrocarbon ?
21. When 8.00 g of hydrogen gas reacts with 38.0 g of fluorine gas in an explosion H2 + F2 ------> 2HF the final gas mixture will contain:
22. In order to dilute 250.0 cm3 of 0.400 mol dm-3 HCl to 0.100 mol dm-3, the volume of water which must be added is : A. 250 cm3
23. A hydrated salt was found to contain 14.75 % water. The mass analysis of the anhydrous salt gave the following results : Ba 65.86 % ; Cl 34.14 % The formula of the original compound is : A. BaCl2.4H2O
24. Which solution contains the same number of ions per dm3 as 0.10 mol dm-3 Al2(SO4)3(aq) ? (aq)
25. Calculate the mass of hydrogen formed when 5.4 g of Al reacts with excess HCl.
26. An unknown element X combines with oxygen to form a compound which has the formula X2O3. It is found that 14.0 g of the element combines exactly with 6.0 g of oxygen to form 20 g of X2O3. What is the relative atomic mass (Ar) of X?
27. If 250 cm3 of 1.0 mol dm-3 MgCl2 is diluted to 1.00 dm3, the number of moles of chloride ion present, and the concentration of chloride ions in the resulting solution resulting solution are :
28. When the equation below is balanced the using the simplest whole number coefficients, the sum of the coefficients is ? (Do not forget coefficients of one).
29. When the equation below is balanced the using the simplest whole number coefficients, the sum of the coefficients is ? (Do not forget coefficients of one).
30. 100 g of a mixture of CaCO3(s) + CaO(s) was completely decomposed by heat leaving 64.8 g of CaO(s).
The mass % of CaCO3(s) in the mixture was :
31. The concentration of SO42- ions in 250 cm3 of 0.30 mol dm-3 Al2(SO4)3 solution is :
32. A sample of magnesium carbonate in a crucible (total mass = 121 g) is decomposed by heat. The mass of magnesium oxide and crucible obtained is 110 g.
What was the mass of the crucible ?
33. 0.69 g of the carbonate of a Group I metal reacted with exactly 10 cm3 of a solution of HCl of concentration 1.0 mol dm-3 according to the equation.
The group I metal could have been :
34. In performing an acid – base titration, a pipette, burette and conical flask are to be used. Which of these should be rinsed with the solution that they are to contain, rather than water, before performing the titration ?
35. A 366 g sample of KBrO4 (Mr = 183) was decomposed by heating producing a solid residue of mass 238 g. Which is the equation which corresponds to this decomposition ?
36. 1 dm3 of NaOH(aq), concentration 1.0 mol dm-3, is mixed with 1 dm3 of HCl(aq), concentration 2.0 mol dm-3. After reaction, the resulting solution :
37. An excess of aqueous barium chloride was added to an aqueous solution containing 32.2 g of Na2SO4.xH2O. 0.100 mol of BaSO4 was precipitated. The value of x is
38. A student mixed 800 cm3 of HCl(aq), concentration 0.600 mol dm-3 with 1200 cm3 of HCl(aq), concentration 0.200 mol dm-3. The resulting solution would have a concentration of HCl(aq) of:
39. An element X forms three different compounds whose relative molecular masses, and the mass percentage of X in each are given below
Compound relative molecular mass % by mass of X 1 100 42 2 56 50 3 224 25 The most likely value for the relative atomic mass of X is:
40. A concentrated aqueous solution of HNO3 has a density of 1.42 g cm-3, and contains 70% by mass of HNO3. Determine the concentration of HNO3 in mol dm-3.
|
Check your answers here