Class 10 Science 2. Acids, Bases and Salts Unit Test Papers

Chapter 2. Acids, Bases and Salts

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Q1. Name two organic acids.

      दो जैविक अम्लों के नाम बताइए |

Q2. How does baking powder differ from baking soda?

       बेकिंग सोडा बेकिंग पावडर से अलग कैसे है ? 

Q3. What will happen if heating is not controlled while preparing plaster of Paris.

       क्या होगा जब प्लास्टर ऑफ़ पेरिस बनाते समय ऊष्मा नियंत्रित न हो | 

Q4. A housewife found that the cake prepared by her is hard and small in size. Which ingradient has she forgotten to add that would have made the cake fluffy. Give reason.

 एक गृहणी से पाया कि उसके द्वारा केक बनाते समय केक छोटा एवं कठोर रह गया है | वह कौन सा संघटक वह डालना भूल गयी थी जिससे यह केक फुला हुआ बन जाता | कारण दीजिए | 

Or 

A baker found that the cake prepared by him is hard and small in size. Which ingredients has he forgotten to add that would have caused the cake to rise and become light?

Q5. What is water of crystallization? Name two hydrated salts.

       जल के क्रिष्टिलीकरण क्या है ? दो हाइड्रेट लवणों का नाम दीजिए | 

Q6. What happens when an acid reacts with a base? Give equation of the reaction of the reaction involved. What is the special name of this reaction?

       क्या होता है जब कोई अम्ल किसी क्षारक के साथ अभिक्रिया करता है ? इस प्रकार के होने वाले अभिक्रिया का समीकरण लिखिए | इस अभिक्रिया का विशेष नाम क्या है ? 

Q7. Explain how pH changes in the river water can endanger the lives of aquatic animals.

       समझाइए कि कैसे नदी के जल का pH बदल जाता है और यह जलीय जीवों के जीवन के लिए कैसे खतरनाक है ?  

Q8. 

Q9. What are the two main ways in which common salt (sodium chloride) occurs in nature? How is common salt obtained from sea water? Explain.

      वे दो तरीकें कौन-कौन से है जिसमें साधारण नमक (सोडियम क्लोराइड) प्रकृति में बनता है ? साधारण नमक समुद्र से जल से कैसे प्राप्त होता है ? समझाइए | 

Q10. What happens when

(a) Solid sodium hydrogen carbonate is heated,

(b) Chlorine gas is passed through dry slaked lime,

(c) Gypsum is heated to a temperature of 373 K?

      क्या होता है जब 

(a) ठोस सोडियम हाइड्रोजन कार्बोनेट को गर्म किया जाता है | 

(b) शुष्क बुझे हुए चुने से क्लोरीन गैस प्रवाहित किया जाता है |

(c) 373 K के तापमान पर जिप्सम को गर्म किया जाता है | 

Q11. Answer the following;

(i) What is a salt?

(ii) Why aqueous solution of sodium carbonate is basic in nature?

(iii)Why is an aqueous solution of ammonium chloride acidic in nature?

निम्न प्रश्नों का उत्तर दीजिए | 

Q12. A milkman adds a very small amount of baking soda to fresh milk.

Q13. Why do acids not show acidic behaviour in the absence of water?

Q14. Alcohols and Glucose contain hydrogen but are not categorized as acids.

Q15. Plaster of Paris should be stored in a moisture-proof container. Explain why?

Q16. Why is calcium sulphate hemihydrates called 'Plaster of Paris'?

Q17. Equal lengths of the magnesium ribbons are taken in test tubes A and B. Hydrochloric acid (HCl) is added to test tube A, while acetic acid (CH3COOH) is added to test tube B. In which test tube will the fizzing occur more vigorously and why?

Q18. Name a solution reacts with crushed egg-shells to give a gas that lime-water milky.

Q19. Why does distilled water not conduct electricity, whereas rain water does.

Q20. What is aqua-regia ?

Q21. Name the sodium compound which is used for softening hard water.

Q22. Why should curd and sour substances not be kept in brass and copper vessels?

Q23. What is efflorescence?

Q24. What are the components of baking powder? 

Q25. Three solutions A, B and C have pH, values of 6, 4 and 10 respectively. Which of the solution is highly acidic?

Q26. Two solutions X and Y have pH = 4 and pH = 8 respectively. Which solution will give alkaline reaction and which one acidic.

Q27. A farmer has found that the pH of soil in his fields is 4.2. Name any two chemical materials which he can mix with soil with soil to adjust its pH.

Q28. State the chemical name and formula of common salt.

Q29. ‘Sweet tooth’ may lead to tooth decay. Explain why? What is the role of tooth paste in preventing cavities?

Q29. Write the reaction that takes place when sodium oxide reacts with water. How will this solution behave towards phenolphthalein and red litmus paper?

Q30. Why should curd and sour substances not be kept in brass and copper vessels? (2 marks) 8. How is the concentration of hydronium ions (H2O+) affected when a solution of an acid is diluted?

Q31. Why do acids not show acidic behavior in the absence of water?

Q32. Identify the compound of calcium which is used for plastering of fractured bones. With the help of chemical equation, describe how this compound is prepared. What special precaution should be taken during the preparation of this compound?

Q33. State Arrhenius Concept of acids and bases. Giving reason, select a strong acid and a weak base from amongst the following substances:

H2CO3, HNO3, NaOH, NH4OH

Q34.

(i) Why should curd and sour substances no be kept in brass and copper vessels.

(ii) The pH of hydrochloric acid solution is 3. Does it mean that it has only hydronium ions. If not, how are OH^- ions generated?

(iii) Distinguish between acid and alkali.  Or Compounds like alcohol and glucose also contain hydrogen but are not categorized as acids. Describe an activity to prove it.