The Amazing World of Solutes, Solvents and Solutions — Class 8 MCQs with Answers
Class 8 CBSE Science · Chapter 9
72 practice questions · 24 Easy · 24 Medium · 24 Hard · Updated
Practise the most important Class 8 CBSE Science questions from Chapter 9, "The Amazing World of Solutes, Solvents and Solutions". You get 9 timed quizzes made from 72 NCERT-based MCQs, with answers and explanations. The questions are split into 24 Easy, 24 Medium and 24 Hard. Warm up on the basics, then move on to the exam-level questions that top scorers in CBSE Board exams get right.
To score well in "The Amazing World of Solutes, Solvents and Solutions", focus on clear concepts in physics, chemistry and biology basics. Each MCQ here is timed and uses exam-style marking (+4 correct, −1 wrong, 0 skipped). This helps you stay accurate when time is short, just as real papers need. Every question has a short explanation, so a wrong answer becomes a quick lesson. It is the fastest way to fix gaps before a test.
Use this chapter for focused revision. Start with the Easy set to check your basics on The Amazing World of Solutes, Solvents and Solutions, then move to Medium and Hard to practise applying them. Your accuracy, streaks and XP save automatically. This chapter also adds to your overall Class 8 Science mastery score. 14 sample questions are solved in full below, with the answer and a worked explanation. Sign in free to start practising.
The Amazing World of Solutes, Solvents and Solutions — important questions & MCQs with answers (Class 8 Science)
14 solved questions from this chapter's difficulty levels, each with its answer and explanation.
- Q1Easy
The substance that dissolves in a liquid is the:
A.solventB.solute✓ CorrectC.solutionD.mixtureAnswer: B. solute
Explanation: The substance that dissolves is called the solute — sugar in tea, salt in water. The liquid doing the dissolving plays a different role, the solvent.
- Q2Easy
A solution in which more solute can still dissolve at a given temperature is:
A.saturatedB.only diluteC.unsaturated✓ CorrectD.only concentratedAnswer: C. unsaturated
Explanation: An unsaturated solution can still take up more solute at that temperature, unlike a saturated one which has reached its limit.
- Q3Easy
A mixture whose components are evenly spread and not visible separately is:
A.non-uniformB.always a suspensionC.a compoundD.uniform (a solution)✓ CorrectAnswer: D. uniform (a solution)
Explanation: When a mixture's components are spread evenly and cannot be seen separately, it is uniform — a solution. A non-uniform mixture shows visible parts.
- Q4Easy
The mass present in a unit volume of a substance is its:
A.weightB.solubilityC.density✓ CorrectD.temperatureAnswer: C. density
Explanation: Density is the mass present in a unit volume of a substance, calculated as mass divided by volume — not the same as weight or solubility.
- Q5Easy
The liquid in which a substance dissolves is the:
A.solvent✓ CorrectB.soluteC.solutionD.suspensionAnswer: A. solvent
Explanation: The liquid that dissolves a substance is the solvent — water is the most common one. The dissolved substance itself is the solute, a separate role.
- Q6Easy
A solution in which no more solute can dissolve (extra settles) is:
A.unsaturatedB.diluteC.emptyD.saturated✓ CorrectAnswer: D. saturated
Explanation: A saturated solution holds the maximum solute it can at that temperature; any extra added simply settles instead of dissolving.
- Q7Medium
If you keep adding salt to water until no more dissolves, you have made a:
A.unsaturated solutionB.dilute solutionC.saturated solution✓ CorrectD.gasAnswer: C. saturated solution
Explanation: Once you keep adding salt and no more dissolves, the solution has reached its limit at that temperature and is saturated.
- Q8Medium
Which of these is a solution?
A.sugar dissolved in water✓ CorrectB.sand in waterC.oil in waterD.chalk powder in waterAnswer: A. sugar dissolved in water
Explanation: Sugar dissolved in water forms a true solution because it disperses evenly at the molecular level; sand, oil and chalk powder stay visibly separate instead.
- Q9Medium
A block has a mass of 20 g and a volume of 10 cm³. Its density is:
A.200 g/cm³B.2 g/cm³✓ CorrectC.0.5 g/cm³D.30 g/cm³Answer: B. 2 g/cm³
Explanation: Density = mass ÷ volume = 20 g ÷ 10 cm³ = 2 g/cm³.
- Q10Medium
One spoon of salt in a glass of water is more ___ than five spoons in the same water.
A.dilute✓ CorrectB.concentratedC.saturatedD.solidAnswer: A. dilute
Explanation: With only one spoon of salt in a glass of water, there is far less solute than in the five-spoon version, making it the more dilute solution.
- Q11Medium
A uniform mixture is also called a:
A.suspensionB.compoundC.elementD.solution✓ CorrectAnswer: D. solution
Explanation: A mixture that is uniform throughout, with no visible separate parts, is called a solution — not a suspension, compound or element.
- Q12Hard
The best one-line summary of this chapter is:
A.it is only about saltB.it studies how substances dissolve, and why things float or sink (density)✓ CorrectC.it is only about gasesD.matter has no propertiesAnswer: B. it studies how substances dissolve, and why things float or sink (density)
Explanation: This chapter covers two connected ideas: how solutes dissolve in solvents to form solutions of varying concentration, and how density explains why objects float or sink.
- Q13Hard
To dissolve the most sugar in water, you should use water that is:
A.hot✓ CorrectB.ice-coldC.frozenD.boiling then frozenAnswer: A. hot
Explanation: Hot water has higher solubility for sugar than cold water, so heating the water before adding sugar lets the most dissolve.
- Q14Hard
Aquatic animals struggle in very warm water because warm water:
A.holds less dissolved oxygen✓ CorrectB.holds more oxygenC.has no waterD.turns to iceAnswer: A. holds less dissolved oxygen
Explanation: Very warm water holds less dissolved oxygen than cool water, leaving aquatic animals with less oxygen available to breathe.
Key concepts: The Amazing World of Solutes, Solvents and Solutions (Class 8 Science)
This chapter explores how substances dissolve and why things float or sink. When a solute dissolves in a solvent it forms a solution — a uniform mixture. Solubility is the maximum solute that dissolves in a fixed amount of solvent at a given temperature, and a solution is saturated when no more will dissolve. The solubility of most solids rises with temperature, while gases dissolve less as water warms, which matters for the dissolved oxygen that keeps aquatic life alive. The chapter also defines density (Density = Mass ÷ Volume) and uses it to explain that objects less dense than a liquid float, while denser ones sink.
- Solute, solvent, solution
- The solute is the substance that dissolves, the solvent is the liquid it dissolves in (present in the larger amount), and together they make a solution.
- Solubility
- The maximum amount of a solute that dissolves in a fixed quantity of solvent at a given temperature.
- Saturated and unsaturated
- A saturated solution can dissolve no more solute at that temperature; an unsaturated one can still dissolve more.
- Concentration
- How much solute is present in a solution; a dilute solution has little solute and a concentrated solution has a lot.
- Temperature and solids
- The solubility of most solids increases as the temperature rises, so a saturated solution can dissolve more when heated and may crystallise when cooled.
- Solubility of gases
- Gases dissolve in water only a little and their solubility decreases as temperature rises, so cold water holds more dissolved oxygen for aquatic life than warm water.
- Uniform and non-uniform mixtures
- A uniform (homogeneous) mixture is a solution whose components are not visible separately; in a non-uniform mixture, like sand in water, the parts can be seen.
- Density
- The mass present in a unit volume of a substance, Density = Mass ÷ Volume; it depends on the material, not on the shape or size, and its SI unit is kg/m³ (water is about 1 g/cm³).
- Relative density
- The density of a substance compared with the density of water — its density divided by that of water.
- Floating and sinking
- An object floats in a liquid if it is less dense than the liquid and sinks if it is denser, which is why oil floats on water and a stone sinks.
- Density and temperature
- Heating usually expands a substance and lowers its density; water is unusual in having its greatest density at 4 °C.
Start this chapter free
You have 14 solved above. Sign in with Google (no card needed). You get 1 Easy + 1 Medium quiz on every chapter during your 30-day trial. After that, you keep 1 Easy quiz on every chapter, free for good, plus the formulas & exam tips.
This chapter has 72 questions (24 Easy · 24 Medium · 24 Hard), with timed scoring and instant feedback. The rest unlock with the ₹999/year plan.
Start this chapter free →The Amazing World of Solutes, Solvents and Solutions — FAQs
What are the key concepts in Class 8 Science The Amazing World of Solutes, Solvents and Solutions?+
This chapter explores how substances dissolve and why things float or sink. When a solute dissolves in a solvent it forms a solution — a uniform mixture. Solubility is the maximum solute that dissolves in a fixed amount of solvent at a given temperature, and a solution is saturated when no more will dissolve. The solubility of most solids rises with temperature, while gases dissolve less as water warms, which matters for the dissolved oxygen that keeps aquatic life alive. The chapter also defines density (Density = Mass ÷ Volume) and uses it to explain that objects less dense than a liquid float, while denser ones sink. Key ideas include Solute, solvent, solution, Solubility, Saturated and unsaturated, Concentration, Temperature and solids, Solubility of gases.
What does Class 8 Science Chapter 9 (The Amazing World of Solutes, Solvents and Solutions) cover on XamBaaz?+
It has 72 NCERT-based MCQs on "The Amazing World of Solutes, Solvents and Solutions": 24 Easy, 24 Medium and 24 Hard. Together they make 9 timed quizzes, and you never get the same set twice. Every question has an instant explanation. They help you prepare for CBSE Board exams.
Are these "The Amazing World of Solutes, Solvents and Solutions" questions free to practise?+
Yes. Sign in with Google to practise "The Amazing World of Solutes, Solvents and Solutions" free. Full unlimited access is ₹999/year. One year from the day you pay. You stay in Class 8 till 31 March; on 1 April your account moves up to Class 9 and the rest of your year carries over. No chapter is charged separately.
How should I revise "The Amazing World of Solutes, Solvents and Solutions" for the exam?+
Start with the Easy quiz to check your basics, then try Medium and Hard to practise applying them. There are 9 timed quizzes on this chapter, so you can come back for a fresh set instead of one you have seen. Read each explanation, retry the questions you miss, and track your accuracy until it stays high.
Are these "The Amazing World of Solutes, Solvents and Solutions" MCQs available with answers?+
Yes. 14 sample questions are shown here in full, each with the correct option and a step-by-step "Why" explanation. Sign in free with Google to start practising, with instant scoring.
Is there negative marking in the "The Amazing World of Solutes, Solvents and Solutions" quizzes?+
Yes. The timed quizzes use exam-style marking: +4 for a right answer, −1 for a wrong one and 0 for a skip. MHT-CET and CBSE board papers have no negative marking. Our mocks for those are scored their way.
What are the important questions from The Amazing World of Solutes, Solvents and Solutions (Class 8 Science)?+
The questions that matter most test Solute, solvent, solution, Solubility, Saturated and unsaturated, Concentration, Temperature and solids, Solubility of gases. This page shows 14 solved important MCQs with answers and explanations. Sign in to practise all 72 questions on the chapter as timed quizzes.
Is there an online quiz for The Amazing World of Solutes, Solvents and Solutions?+
Yes — Class 8 Science The Amazing World of Solutes, Solvents and Solutions has timed online quizzes at Easy, Medium and Hard levels, with instant scoring and a worked explanation on every question. The first quiz on the chapter is free.