How would you confirm that a colorless liquid given to you is pure water?
Solution and Explanation
If the given colorless liquid boils at 100°C sharp, it is pure water, otherwise not.
Top Questions on Physical and Chemical Changes
- Which of the following is a chemical transformation?
- UPCATET - 2024
- Chemistry
- Physical and Chemical Changes
- The hot food prepared in the kitchen can be smelt outside the house because of :
- CET Delhi Polytechnic - 2017
- Chemistry
- Physical and Chemical Changes
Pragya tested the solubility of three different substances at different temperatures and collected the data as given below (results are given in the following table, as grams of substance dissolved in 100 grams of water to form a saturated solution).
Substance Dissolved Temperature in K
283
293
313
333
353
Solubility
Potassium nitrate 21 32 62 106 167 Sodium chloride 36 36 36 37 37 Potassium chloride 35 35 40 46 54 Ammonium chloride 24 37 41 55 66 (a) What mass of potassium nitrate would be needed to produce a saturated solution of potassium nitrate in 50 grams of water at 313 K?
(b) Pragya makes a saturated solution of potassium chloride in water at 353 K and leaves the solution to cool at room temperature. What would she observe as the solution cools? Explain.
(c) Find the solubility of each salt at 293 K. Which salt has the highest solubility at this temperature?
(d) What is the effect of change of temperature on the solubility of a salt?- CBSE Class IX
- Science
- Physical and Chemical Changes
- Which of the following are chemical changes?
(a) Growth of a plant
(b) Rusting of iron
(c) Mixing of iron filings and sand
(d) Cooking of food
(e) Digestion of food
(f) Freezing of water
(g) Burning of a candle- CBSE Class IX
- Science
- Physical and Chemical Changes
Questions Asked in CBSE Class IX exam
- In the given figure, if AB \(||\) CD, CD \(||\) EF and y: z = 3: 7, find x.
- CBSE Class IX
- Lines Parallel to the Same Line
∆ABC is an isosceles triangle in which AB = AC. Side BA is produced to D such that AD = AB (see Fig. 7.34). Show that ∠ BCD is a right angle.
- CBSE Class IX
- Some Properties of a Triangle
A driver of a car travelling at \(52\) \(km \;h^{–1}\) applies the brakes Shade the area on the graph that represents the distance travelled by the car during the period.
Which part of the graph represents uniform motion of the car?- CBSE Class IX
- Graphical Representation of Motion
- Name the following.
- Tissue that forms the inner lining of our mouth.
- Tissue that connects muscle to bone in humans.
- Tissue that transports food in plants.
- Tissue that stores fat in our body.
- Connective tissue with a fluid matrix.
- Tissue present in the brain.
- CBSE Class IX
- Animal Tissues
- (i) His thoughts when he looks into the mirror
(ii) His thoughts when the snake is coiled around his arm- CBSE Class IX
- The snake and the mirror