Education
Class 10 Chemistry Chapter 18 Salts Test 6 | 2027
Grade 10 Chemistry Chapter No 18 Topic 18.4-18.5
Class 10 Chemistry Chapter 18: Salts Class Test 6 is part of the Punjab Board 2027 Model Papers – Chapter-Wise Test Series, prepared to help students practice Chemistry according to the new syllabus issued by PECTAA Punjab. This test covers Textbook Topics 18.4 to 18.5 from Chapter 18: Salts and is useful for revision, self-assessment, and examination preparation. Students can use this Class 10 Chemistry Test 6 to strengthen their understanding of salts and prepare for their matric Chemistry examinations. Explore more Class 10 Chemistry chapter-wise tests, Punjab Board 2027 model papers, and new syllabus study resources on 786Times.com to support your exam preparation.
Tip: in the print window, choose “Save as PDF” as the destination (paper size A4).
Chapter Wise Class Test
T-6
Chapter-18
Salts
1.Which of the following salts is always soluble in water?
(a) NaCl(b) AgCl(c) PbSO4(d) CaCO3
2.Which of the following hydroxides is partially soluble in water?
(a) NaOH(b) KOH(c) Ca(OH)2(d) Al(OH)3
3.Carbonates are generally:
(a) Always soluble(b) Insoluble except Na+, K+, NH4+ salts(c) Gases(d) Highly reactive only
4.The titration method involves the reaction between:
(a) Insoluble acid and base(b) Soluble acid and soluble base(c) Metal and acid(d) Salt and water
5.The solution after reaction in the flask contains:
(a) Only salt(b) Only water(c) Salt and water(d) Acid only
6.Why is the solution cooled after heating to solidify it?
(a) To remove water(b) To form crystals(c) To increase temperature(d) To dissolve salt
7.What is removed during filtration?
(a) Salt(b) Water(c) Excess base or metal(d) Acid
8.Crystals of salt are obtained after:
(a) Boiling strongly(b) Cooling the saturated solution(c) Filtering immediately(d) Adding more acid
Answers: 1-(a) 2-(c) 3-(b) 4-(b) 5-(c) 6-(b) 7-(c) 8-(b)
www.786Times.com
Chapter Wise Class Test
T-6
Chapter-18
Salts
2. Write short answers to any six (6) questions.[6 × 2 = 12]
(i)
What factors affect the solubility of salts?
Ans: (1) Nature of the salt (solute) and of the solvent; (2) temperature – the solubility of most salts increases on heating; (3) presence of a common ion, which lowers solubility.
(ii)
Which chlorides are insoluble in water?
Ans: Silver chloride (AgCl), mercurous chloride (Hg2Cl2) and lead chloride (PbCl2, which dissolves only in hot water).
(iii)
What is the titration method of preparing salts?
Ans: It is the method for preparing soluble salts by reacting a soluble acid with a soluble base (alkali). An indicator is used to find the exact volume needed for neutralization; the reaction is then repeated without indicator and the solution is evaporated and crystallized.
(iv)
Give an example of salt prepared by titration method.
Ans: Sodium chloride (NaCl):
NaOH + HCl → NaCl + H2O
(v)
What is meant by a saturated solution?
Ans: A solution that cannot dissolve any more solute at a given temperature is called a saturated solution.
(vi)
Why are the crystals dried between filter papers?
Ans: To remove the remaining moisture from the crystals without heating them, so that they do not lose their water of crystallization or decompose.
(vii)
How crystals of salt are obtained.
Ans: The salt solution is heated to evaporate water until it becomes saturated, then cooled slowly. Crystals form, which are filtered, washed and dried.
(viii)
Which salt can be used as fungicide?
Ans: Copper sulphate (CuSO4·5H2O).
(ix)
How is barium sulphate prepared in the laboratory?
Ans: By precipitation: solutions of barium chloride and sodium sulphate are mixed. White insoluble BaSO4 separates, and is filtered, washed and dried.
BaCl2 + Na2SO4 → BaSO4↓ + 2NaCl
Note: Attempt any one question.[5 × 1 = 5]
3.
Explain soluble and insoluble salt.
Soluble salts: salts that dissolve in water, e.g. NaCl, KNO3, CuSO4.
Insoluble salts: salts that do not dissolve in water, e.g. AgCl, BaSO4, CaCO3.
Insoluble salts: salts that do not dissolve in water, e.g. AgCl, BaSO4, CaCO3.
- All nitrates, and salts of Na+, K+, NH4+, are soluble.
- Most chlorides are soluble except AgCl, Hg2Cl2, PbCl2.
- Most sulphates are soluble except BaSO4, PbSO4; CaSO4 is slightly soluble.
- Carbonates are insoluble except those of Na+, K+, NH4+.
4.
Explain the methods of preparation of any one soluble salts.
Titration method (preparation of NaCl):
- Measure 25 cm3 of NaOH solution with a pipette into a conical flask; add 2–3 drops of indicator.
- Add HCl from the burette until the indicator just changes colour (neutralization); note the volume.
- Repeat with the same volumes but without indicator.
- Heat the solution to evaporate water until it becomes saturated.
- Cool it to form crystals; filter, wash and dry them between filter papers.
786Times
