Post Utme Chemistry Questions
Question 21:
Which of the following is an example of a double salt
- A \(\mathrm{NH}_{4} \mathrm{Cl}\)
- B Alum
- C \(\mathrm{NaCO}_{3}\)
- D \(\mathrm{AlCl}_{3}\)
- E \(\mathrm{NaCl}\)
Question 22:
Which of the following ions is isoelectronic with neon? [3Li, 9F, \(10 \mathrm{Ne}, 17 \mathrm{Cl}, 19 \mathrm{~K}]\)
- A \(\mathrm{Cl}-\)
- B F-
- C \(\mathrm{K}+\)
- D Li+
Question 23:
Which of the following gases is employed as an anaesthesia?
- A \(\mathrm{NH}_{3}\)
- B NO
- C \(\mathrm{N}_{2} \mathrm{O}\)
- D \(\mathrm{NO}_{2}\)
Question 24:
Aluminium is extracted commercially from its ore by ____________
- A Heating aluminium oxide with coke in a furnace
- B The electrolysis of fused aluminium oxide in cryolite
- C Treating cryolite with sodium hydroxide solution under pressure
- D Heating sodium aluminium silicate to a high temperature
Question 25:
The atomic number of Caesium is 55 and its atomic mass is ____________
- A 78 protons and 55 electrons
- B 55 protons and 78 neutrons
- C 55 neutrons and 78 electrons
- D 78 neutrons and 55 neutrons