Learn more about the properties, composition, and structure of substances (elements and compounds) with these Chemistry questions and answers. This Test can be used by students preparing for Chemistry in JAMB, WAEC, NECO or Post UTME.
Which of the following types of bonding does not involve the formation of new substances?
Metallic
Covalent
Co-ordinate
Electrovalent
Correct answer is A
Metallic bond does not involve the formation of a new substance. It is responsible for several characteristic properties of metals such as their shiny lustre, their malleability, and their conductivities for heat and electricity
24,125 C
48,250 C
72,375 C
96,500 C
Correct answer is B
4OH ⇒ 2H\(_2\)O + O\(_2\) + 4e-
From the equation:
1 mole of Oxygen requires 4e
i.e 1 mole of Oxygen requires 4F,
where 1F = 96,500 C
[ 4 X 96,500 X 0.125 ] ÷ 1
= 48,250 C
MCl
MCl\(_2\)
MCl\(_3\)
M\(_2\)Cl\(_6\)
Correct answer is C
| M | Cl | |
| % composition | 20.22 | 79.78 |
| Atomic mass | 27 | 35.5 |
| Mole ratio | 20.22 | 79.78 |
| 27 | 35.5 | |
| 0.75 | 2.25 | |
| Divided | 0.75 | 0.75 |
| 1 | 3 |
The formula of the Chloride = MCl\(_3\)
26.0kj/mol
65.0kj/mol
130.0kj/mol
260.0kj/mol
Correct answer is B
32g of CUSO\(_4\) liberate 13.0kj of heat
Molar mass of CUSO\(_4\) = 160g
No. of moles of CUSO\(_4\) = 32g
No. of moles = 32(mass) / 160(molar mass)
= 0.2 moles
i.e 0.2 = 13kj
1 moles = xkj
: 65KJ
Helium is used in observation of ballons because it is?
Light and combustible
light and non-combustible
heavy and combustible
heavy and non-combustible
Correct answer is B
Helium floats because it is buoyant; its molecules are lighter than the nitrogen and oxygen molecules of our atmosphere and so they rise above it