A periodic table is needed for this question
A compound has an empirical formula of C2H6O and a molar mass of 92.16.
What is the molecular formula of this compound?
C2H6O
C4H12O2
C6H18O3
C8H24O4
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Syllabus Edition
First teaching 2014
Last exams 2024
A periodic table is needed for this question
A compound has an empirical formula of C2H6O and a molar mass of 92.16.
What is the molecular formula of this compound?
C2H6O
C4H12O2
C6H18O3
C8H24O4
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Which equation below represents deposition?
2Al(s) + 3Br2(g) → 2AlBr3(s)
MgCO3(s) + 2HCl(aq) → MgCl2(aq) + CO2(g) + H2O(l)
I2(g) → I2(s)
HgCl2(s) → HgCl2(g)
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Below are three statements about mixtures. Which of them are correct?
I Mixtures can contain elements and compounds.
II The components of a mixture must be in the same state.
III The components of a mixture keep their own properties.
I and II only
I and III only
II and III only
I, II and III
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Which box shows a heterogeneous mixture?
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Ethane has the formula C2H6. What is the mass in grams of one molecule of ethane?
(RAMs: C = 12.0; H = 1.0)
1.8 x 1025
3.0 x 10-23
30.0
5.0 x 10-23
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Shown below are four molecular formulas. Which one is also an empirical formula?
PCl5
CH3COOH
H2O2
C6H12O6
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The relative atomic mass is a way of representing the mass of an atom.
Which of the following definitions is correct for the term relative atomic mass?
the mass of an electron
1/12 the mass of a carbon-12 atom
the mass of a hydrogen-1 atom
the mass of a proton
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A periodic table is needed for this question
Which of the following shows the relative formula mass of ammonium sulfate, (NH4)2SO4?
70.00
132.00
114.09
132.17
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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 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 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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A sample of hydrated calcium sulfate, CaSO4∙H2O, has a relative formula mass of 172.19
What is the value of ?
1
2
3
4
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Oxidation of ammonia by oxygen is the first step in the manufacture of nitric acid, which is used in the production of the synthetic material nylon.
wO2(g) + xNH3(g) → yNO(g) + zH2O(g)
Which values for w, x, y and z balance this equation?
|
w |
x |
y |
z |
A B C D |
5 6 6 5 |
4 4 5 6 |
4 4 5 6 |
6 5 4 4 |
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A compound of molar mass 92 gmol-1 contains 12g of carbon, 2g of hydrogen and 32g of oxygen. What is the molecular formula of the compound?
CH2O2
CH2O
C2H4O2
C2H4O4
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When lead sulfide reacts with oxygen it produces lead(II)oxide and sulfur dioxide according to the equation below:
PbS(s) + O2(g) → PbO(s) + SO2(g)
What is the whole number sum of the coefficients in the balanced equation?
4
5
8
9
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A compound is made of sulfur and oxygen only. A sample of the compound has a mass of 8.0g, and consists of 3.2g of sulfur and 4.8g of oxygen. The empirical formula of the compound is:
(RAMs S = 32.0, O = 16.0)
SO
SO2
SO3
S2O3
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Which of these processes are endothermic?
I. Condensing
II. Subliming
III. Melting
I and II only
I and III only
II and III only
I, II and III
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Ethanoic acid has the formula CH3COOH. How many carbon atoms are present in
0.1 mol of ethanoic acid?
6.0 x 1022
1.2 x 1023
6.0 x 1023
1.2 x 1024
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Which of the following samples has the largest mass?
(RAMs, H = 1.01, N = 14.01, O = 16.00)
2.0 mol of NH4+
1.0 mol of H2S
1.0 mol of H2O2
2.0 mol of OH-
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A compound contains carbon and hydrogen only. The amount of carbon is 80% by mass. What is the empirical formula of the compound?
(RAMs, H = 1.01, C = 12.01)
CH
CH2
CH3
CH4
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A periodic table is needed to answer this question
A hydrated carbonate of an unknown Group 1 metal has the formula X2CO3∙10H2O and is found to have a relative formula mass of 286.19
What is the group 1 metal?
Rb
K
Na
Li
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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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A periodic table is needed to answer this question
A coin contains 5.869% Nickel by mass. If the coin weighs 10.00g, how many Nickel atoms are in the coin?
4.30 x 1022
3.01 x 1023
6.02 x 1025
6.02 x 1021
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The correct combination relating to state change, particles and energy is:
A |
Subliming |
particles move further apart |
particles gain energy |
B |
Vaporizing |
particles come closer together |
particles gain energy |
C |
Melting |
particles move further apart |
particles lose energy |
D |
Condensing |
particles come closer together |
particles gain energy |
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Which of the following mixtures is NOT classified as homogeneous?
Salt solution
Brass
Orange juice that has been filtered
Concrete
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What is the whole number coefficient for oxygen when the equation for the combustion of pentanol is balanced?
C5H11OH(g) + O2 → CO2(g) + H2O(g)
7
8
15
16
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The order in which oxygen, methane, nitrogen and argon will diffuse from slowest to fastest, at the same conditions of temperature and pressure is:
O2 ﹤ N2 ﹤ Ar ﹤ CH4
CH4 ﹤ Ar ﹤ N2 ﹤ O2
N2 ﹤ O2 ﹤ Ar ﹤ CH4
Ar ﹤ O2 ﹤ N2 ﹤ CH4
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What is the total number of protons and electrons in two moles of hydrogen gas?
4
8
2.4 x 1024
4.8 x 1024
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Which sample contains the largest amount, in mol, of atoms?
0.30 mol of P2O5
0.40 mol of CuSO4.5H2O
0.50 mol of CH3COOH
0.90 mol of H2O
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The coefficient for copper when the following equation is balanced is:
_Cu + _HNO3 → _Cu(NO3)2 + _NO + _H2O
1
2
3
4
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Chlorofluorocarbons have been used extensively as liquid coolants in refrigerators and air conditioners. Which of the following descriptions explains how a refrigerant works?
At high pressure the liquid evaporates and absorbs heat, cooling the surroundings
At low pressure the liquid evaporates and absorbs heat, cooling the surroundings
At high pressure the liquid condenses and absorbs heat, cooling the surroundings
At low pressure the liquid condenses and absorbs heat, cooling the surrounding
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Excess dilute hydrochloric acid is added separately to equal masses of the four metals, calcium, zinc, magnesium and strontium. Which metal will give off the largest volume of hydrogen gas in the reaction?
calcium
zinc
magnesium
strontium
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How many ions are present in 0.02 mol of (NH4)3PO4?
8.0 x 10-2
1.2 x 1022
4.8 x 1022
2.4 x 1023
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