WorksheetsCHEMISTRY CONTEST SENIOR CLASSES JUNE 2024
Total questions: 10
Worksheet time: 5mins
0.0625 moles of methane is burnt in air according to the following equation:
CH4 + 2O2 → CO2 + 2H2O
How many moles of Oxygen are required for this combustion reaction?
0.03125
0.0625
0.125
0.25
Assuming that all the chemicals involved in the reaction are in the gaseous state, the balanced symbol equation is:
CH4 + 2O2 → CO2 + 2H2O
What is the total volume of the gas produced when 2500 cm3 of methane is burned?
2500 cm3
5000 cm3
7500 cm3
1000 cm3
Which of the following is a mixture?
Salt
Air
Water
Ammonia
Which one of the following pairs of atoms is most likely to form an ionic bond?
Na and F
C and F
N and F
O and F
Which of the following statement is incorrect?
the greater the number of electrons in a molecule, the greater the van der Waals forces
the layers in graphite are held together by Van der Waals forces
the boiling point of noble gases increases down the group
Water has a higher than expected boiling point because of intermolecular hydrogen bond
Which one of the following statements about negative ions is incorrect?
they are also known as anions
they are formed when atoms gain electrons
they are larger than the atom from which they were formed
they are smaller than the atom from which they were formed.
Which of the following phrases would be used in a description for bonding in BOTH metals and ionic salts:
Strong electrostatic attractions
Ions
Giant Lattice
Delocalized electrons
Which of the following best describes the correct order of oxygen, fluorine, and nitrogen's atomic radii?
O < F < N
N < F < O
F < O < N
O < N < F
A solution of sulphuric (VI) acid, H2SO4, contain 9.8 g of the acid in 250 cm3 of solution.
What is the concentration in mol/dm3?
Relative atomic masses H = 1, S = 32, O = 16
0.10 mol/dm3
0.20 mol/dm3
0.40 mol/dm3
0.80 mol/dm3
The chemical equation for the preparation of lead (II) sulphate is written below.
Pb(NO3)2 (_ _ _) + Na2SO4 (_ _ _) → PbSO4 (_ _ _) + 2NaNO3 (_ _ _)
What are the state symbol for each substances in this reaction?
aq, aq, s, aq
aq, aq, s, s
s, aq, aq, s
s, aq, aq, s, aq
