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.
3.01 x 1022
6.02 x 1022
6.02 x1023
1.20 x 1024
Correct answer is A
32g of sulphur = 64g / 6.02 x 1023 atoms of SO2
xg of sulphur = 3.2g of SO2
: 1.6g of sulphur is present in 3.2g / 3.01 x 1023 atoms of SO2
4.00g
4.44 g
18.9 g
27.8 g
Correct answer is D
CaCO3 + 2HCI → CaCI2 + H2O + CO2
100g CaCO3 will produce 111g CaCI2
25g CaCO3 will produce x ,
x = 25x111100
= 27.75 ≊ 27.8g
MgO does not readily dissolve in water because
of its high melting point
it is a covalent compound
it forms a hydroxide when dissolved in water
its lattice energy is higher than its hydration energy
Correct answer is D
No explanation has been provided for this answer.
The complex compound formed when aluminum dissolves in aqueous sodium hydroxide is
Na3Al(OH)4.
NaAl(OH)4
NaAl(OH)3
Na2Al(OH)3
Correct answer is B
When aluminium is treated with dilute sodium hydroxide it forms a salt called sodium tetrahydroxoaluminate and hydrogen gas.