ECAT Chemistry — Liquids and Solids
Liquids and Solids is part of the Chemistry section of the UET ECAT (30 of the 100 MCQs). It breaks into 3 subtopics, and we hold 46 ECAT-pattern practice MCQs on it, each with a written explanation. Tap a subtopic below to practise just that.
Subtopics (3)
How Liquids and Solids is tested
Across the 7 ECAT past papers on ParhaiKrlo, Liquids and Solids accounts for 23 questions. It appears in all 7, about 3.3 questions a paper. The heaviest was ECAT Past Paper 04, with 5 questions, and the most recent is ECAT Past Paper 07, with 3.
| Paper | Questions |
|---|---|
| ECAT Past Paper 07 | 3 |
| ECAT Past Paper 06 | 3 |
| ECAT Past Paper 05 | 2 |
| ECAT Past Paper 04 | 5 |
| ECAT Past Paper 03 | 3 |
| ECAT Past Paper 02 | 3 |
| ECAT Past Paper 01 | 4 |
Liquids and Solids MCQs from the ECAT past papers
Try each one before opening the answer. Each comes with a short explanation.
- Q1 · ECAT Past Paper 07 · Liquids and Solids
The forces which make the liquefaction of helium gas possible are:
- A.Debye forces
- B.London dispersion forces
- C.Dipole–dipole forces
- D.Liquefaction is not possible
Show answer
Answer: B. London dispersion forces — Helium atoms are non-polar; only weak London forces act between them, allowing liquefaction at about 4 K.
- Q2 · ECAT Past Paper 06 · Liquids and Solids
A crystal system with a = b ≠ c and α = β = γ = 90° is:
- A.Cubic
- B.Tetragonal
- C.Orthorhombic
- D.Hexagonal
Show answer
Answer: B. Tetragonal — Tetragonal: two equal axes, a different third axis, all angles 90°.
- Q3 · ECAT Past Paper 05 · Liquids and Solids
Which of the following, in the solid state, consists of molecules held together by van der Waals forces?
- A.H₂O
- B.Cu
- C.CO₂
- D.MgO
Show answer
Answer: C. CO₂ — Solid CO₂ (dry ice) is a molecular solid whose non-polar molecules are held by van der Waals forces.