The atomic mass is a way of representing the mass of an atom.
Which of the following definitions is correct for the term atomic mass?
The mass of an electron
1/12 the mass of carbon-12 atom
The mass of hydrogen-1 atom
The mass of a proton
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Elements can be found to have different isotopes.
What is different about the nuclei of isotopes?
The same number of protons, but different number of neutrons
The same number of protons, and the same number of neutrons
A different number of protons, and a different number of neutrons
A different number of protons, and the same number of neutrons
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Which of the following show the relative formula mass of ammonium sulfate, (NH4)2SO4?
Use of the data booklet is relevant to this question.
98.1
98
132.1
132
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Iron has many different naturally occurring isotopes.
|
Isotope |
% Abundance |
Atomic mass |
|
54Fe |
5.845 |
53.9396 |
|
56Fe |
91.754 |
55.9349 |
|
57Fe |
2.119 |
56.9354 |
|
58Fe |
0.282 |
57.9333 |
Using the information given, what is the average atomic mass of iron?
56.1858 amu
55.500 amu
59.270 amu
55.845 amu
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Use of the data booklet is relevant to this question
What is the number of molecules in 500 cm3 of oxygen at standard temperature and pressure?
3.00 x 1023
3.00 x 1026
1.25 x 1021
1.34 x 1022
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When the following equation is balanced correctly, using the smallest whole number coefficients, which row represents the coefficients?
__ Mg3N2 (s) + __H2O (l) → __Mg(OH)2 (aq) + __NH3 (aq)
|
Mg3N2 |
H2O |
Mg(OH)2 |
NH3 |
|
|
A |
1 |
6 |
3 |
2 |
|
B |
1 |
3 |
3 |
1 |
|
C |
2 |
6 |
2 |
2 |
|
D |
2 |
6 |
3 |
2 |
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Which one of the following is the correct net ionic equation for the reaction (if one occurs) between CaCl2 and AgNO3?
Ca2+ (aq) + 2AgNO3 (aq) → 2Ag+ (s) + Ca(NO3)2 (aq)
CaCl2 (aq) + 2Ag+ (aq) → 2AgCl (s) + Ca2+ (aq)
Ca2+ (aq) + 2NO3- (aq) → Ca(NO3)2 (aq)
Ag+ (aq) + Cl- (aq) → AgCl (s)
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Which one of the following is the correct net ionic equation for the reaction (if one occurs) between NaC2H3O2 (aq) and HCl (aq)?
C2H3O2- (aq) + HCl (aq) → CCl- (aq) + 2H2 (aq) + CO2 (aq)
C2H3O2- (aq) + H+ (aq) → HC2H3O2 (aq)
Na+ (aq) + Cl- (aq) → NaCl (aq)
NaC2H3O2 (aq) + H+ (aq) → HC2H3O2 (aq) + Na+ (aq)
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Use of the data booklet is relevant to this question.
A compound was found to be 52.2% by weight carbon, 13.0% hydrogen and 34.8% oxygen.
What is the empirical formula of this compound?
C2H4O2
C4H13O2
C2H6O
C6H2O
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Use of the data booklet is relevant to this question.
A sample of hydrated calcium sulfate, CaSO4∙xH2O, has a relative formula mass of 172.2
What is the value of x?
1
2
3
4
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A hydrated carbonate of an unknown Group 1 metal has the formula X2CO3∙10H2O and is found to have a relative formula mass of 286.
What is the group 1 metal?
Rb
K
Na
Li
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A volume of nitrogen gas, 2.00 dm3 measured under standard conditions, was reacted with a large volume of hydrogen gas, to produce ammonia. Only 15.0% of the nitrogen gas reacted to produce ammonia.
What mass of ammonia was made?
2.83 g
1.42 g
0.455 g
0.213 g
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Excess aqueous cold sodium hydroxide is reacted with 0.125 mol of chlorine gas, Cl2. One of the products is a compound of sodium, oxygen and chlorine.
What mass of the product is formed?
13.3 g
9.31 g
18.6 g
26.6 g
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The diagram below shows the skeletal formula of phenazine.
What is the empirical formula of phenazine?
C6H6N
C12H8N2
C6H4N
C12H12N2
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Use of the data booklet is relevant to this question.
When heated magnesium nitrate, Mg(NO3)2, will decompose to a white solid and a mixture of gases. One of the gases released is an oxide of nitrogen, X.
7.4 g of anhydrous magnesium nitrate is heated until no further reaction takes place.
What is the mass of X produced?
4.6 g
1.5 g
2.3 g
3.0 g
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Use of the data booklet is relevant to this question.
Excess water and 0.144 g of an aluminium compound X were reacted to form a gas. The gas burns completely in O2 to form H2O and 72 cm3 of CO2 only. The volume of CO2 was measured at room temperature and pressure.
What is the formula for X?
Al2C3
Al3C4
Al5C3
Al4C3
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A metal element of mass 1.15 g reacted with 300 cm3 of oxygen at 298 K and 1 atm pressure, to form an oxide which contains O2- ions.
Which one of these is the metal?
Calcium
Sodium
Potassium
Magnesium
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The mass of a coin is 20% nickel. The coin has a mass of 10.0 g.
How many nickel atoms are in the coin?
4.30 x 1022
1.03 x 1023
1.20 x 1024
2.05 x 1022
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Use of the data booklet is relevant to this question.
An additive in leaded petrol is composed of lead, carbon and hydrogen only. The compound contains 6.19% hydrogen and 29.7% carbon by mass.
What is the value of x in the empirical formula PbC8Hx?
6
5
20
16
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Use of the data booklet is relevant to this question
Solid fertilisers often contain the elements N, P and K in a ratio of 15 g: 30 g: 15 g per 100 g of fertiliser. It is recommended that the fertiliser is used at 14 g of fertiliser per 5 dm3 of water.
What is the concentration of nitrogen atoms in the solution?
0.42 mol dm-3
0.05 mol dm-3
0.03 mol dm-3
0.75 mol dm-3
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1.00 g of carbon is combusted in a limited supply of oxygen. 0.50 g of the carbon combusts to form CO2 and 0.50 g of the carbon combusts to form CO.
These were passed through excess NaOH (aq) and the remaining gas then dried and collected.
Assuming that all gas volumes were taken at 25˚C and 1 atm pressure, what was the volume of gas at the end of the reaction?
3 dm3
2 dm3
1.5 dm3
1 dm3
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Egg shells make up 5% of the mass of chicken eggs. The average egg has a mass of 50 g.
Assume that chicken eggshell is pure calcium carbonate.
How many complete chicken eggshells would be needed to neutralise 50 cm3 of 2.0 mol dm-3 ethanoic acid?
4
3
2
1
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Use of the data booklet is relevant to this question
When a sample potassium oxide, K2O, is dissolved in 250 cm3 of distilled water. 25 cm3 of this solution is titrated against sulfuric acid with concentration of 2.00 mol dm-3. Complete neutralisation takes place with 15 cm3 of sulfuric acid.
What is the mass of the original sample of potassium oxide dissolved in 250 cm3 of distilled water?
56.6 g
47.1 g
28.3 g
2.83 g
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Iron and chromium can be made into an alloy called ferrochrome. Ferrochrome can be dissolved in dilute sulfuric acid to produce FeSO4 and Cr2(SO4)3. The FeSO4 reacts with K2Cr2O7 in acid shown in this equation:
14H+ + 6Fe2+ + Cr2O72- → 2Cr3+ + 6Fe3+ + 7H2O
1.00g of ferrochrome is dissolved in dilute sulfuric acid, and then titrated, 13.1cm3 of 0.100 mol dm-3 K2Cr2O7 is needed for the complete reaction.
In the sample of ferrochrome, what is the percentage by mass of Fe?
43.9
12.2
4.39
1.22
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10 cm3 of methane and 10 cm3 of ethane were sparked with an excess of oxygen. Once cooled the remaining gas was passed through aqueous potassium hydroxide.
Assuming all measurements were taken at 25˚C and 1 atm pressure.
What volume of gas is absorbed by the alkali?
45 cm3
30 cm3
20 cm3
10 cm3
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A solution of Sn2+ ions will reduce MnO4- ions to Mn2+ ions when acidified. The Sn2+ ions are oxidised to Sn4+ ions in this reaction.
How many moles of Mn2+ ions are formed when a solution containing 9.5 g of SnCl2
(Mr: 190) is added to an excess of acidified KMnO4 solution?
0.010
0.015
0.020
0.050
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Use of the data booklet is relevant to this question
Some fireworks can use the reaction between aluminium powder and anhydrous barium nitrate as a propellant. Metal oxides and nitrogen are the only products.
10Al + 3Ba(NO3)2 → 5Al 2O3 + 3BaO + 3N2
When 0.783 g of anhydrous barium nitrate reacts with an excess of aluminium what is the volume of nitrogen produced?
144.0 cm3
93.6 cm3
1.62 cm3
72.0 cm3
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Excess acidified aqueous potassium dichromate (VI) was mixed with 2.76 g of ethanol. The reaction mixture was then boiled under reflux for one hour. The organic product was collected by distillation.
The yield of the product was 75.0%
What is the mass of the product collected?
1.98 g
2.70 g
2.07 g
4.80 g
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The concentration of calcium ions in a sample of water can be determined by using an ion-exchange column, shown in the diagram below:
A 50 cm3 sample of water was passed through the ion-exchange resin, this contained dissolved calcium sulfate
Each calcium ion in the sample was exchanged for two hydrogen ions. The resulting acidic solution collected in the flask required 25 cm3 of 1.0 x 10-2 mol dm-3 potassium hydroxide for complete neutralisation.
What was the concentration of the calcium sulfate in the original sample?
4.0 x 10-2 mol dm-3
2.0 x 10-2 mol dm-3
1.0 x 10-2 mol dm-3
2.5 x 10-3 mol dm-3
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Bromide ions are oxidised to bromine by lead (IV) chloride. The Pb4+ ions are reduced to Pb2+ ions in this reaction.
If 6.980 g of lead (IV) chloride is added to an excess of sodium bromide solution, what mass of bromine would be produced?
3.196 g
6.392 g
0.799 g
1598 g
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