CBSE ADDA

Guess Question Paper – 2012
Class – X
Subject – Science (Acid,Bases & Salts)

1.What is the colour change when you add blue litmus to sour substances?

2.Name two synthetic indicators.

3.Which acid is present in lemon juice?

4.Baking soda solution can be used as a remedy for which type of ailments?

5.What is meant by neutralization?

6.Name two natural indicators.

7.What is the colour of methyl orange in acidic solution?

8.What is meant by dilution?

9.What is a universal indicator?

10.On what factors does the strength of a base depend?

11.Give example of common antacid.

12.Write the chemical name & formula of bleaching powder.

13.Name the compound used for removing hardness of water.

14.Which gas is released when an acid reacts with a metal?

15.What are the salts of sulphuric acid called?

16.What is difference between washing soda and soda ash?

17.Give one point difference between an alkali and a base.

18.Name the natural source of acetic acid.

19.When metal carbonates react with acids which gas is produced?

20.What do all acids and bases have in common?

21.Give one example of strong acid and weak acid.

22.What is the chemical name of hardest substance in our body?

23.What is dead burnt plaster ?

24.What is milkiness due to when carbon dioxide gas is passed through lime water?

25.What are olfactory indicators ?

26.On what factors does the strength of an acid depend?

27.What happens when metal oxides react with acids?

28.Nmae four families of salts.

29.What happens when sodium hydrogen carbonate is heated?

30.What is the pH range between which our body works?

31.Why is sulphuric acid called king of chemicals?

32.What are anhydrous and hydrated salts? Explain with examples.

33.What is the diiference between a strong base and weak base? Give two example of each.

34.What is deliquescent salt? Give example.

35.Why is tartaric acid added into baking soda to get baking powder?

36.With the help of chemical equation explain how a soda acid fire extinguisher helps in putting out fire.

37.A tarnished copper vessel begins to shine when rubbed with lemon. Why?

38.How is plaster of paris different chemically different from gypsum?How may they be interconverted?

39.What is efflorescence? Give example.

40.Write any three chemical prorerties of acids.

41.What happens when chlorine is passed through slaked lime?

42.Define monobasic, dibasic and tribasic acids.

43Define an acid in terms of ions.

44.What is the role of water in litmus test of an acid?

45.Define base in terms of ions.

46.Differentiate between acids and bases.

Comments

CBSE ADDA :By Jsunil Sir : Your Ultimate Destination for CBSE Exam Preparation and Academic Insights

Class 10 Chapter 02 Acid Bases and Salts NCERT Activity Explanation

NCERT Activity Chapter 02 Acid Bases and Salt Class 10 Chemistry Activity 2.1 Indicator Acid Base Red litmus No Change Blue Blue Litmus Red No change Phenolphthalein Colourless Pink Methyl Orange Pink Yellow Indictors are substance which change colour in acidic or basic media. Activity 2.2 There are some substances whose odour changes in in acidic or basic media. These are called olfactory indicators. Like onion vanilla, onion and clove. These changes smell in basic solution. Activity 2.3 Take about 5 mL of dilute sulphuric acid in a test tube and add few pieces of zinc granules to it. => You will observe bubbles of hydrogen gas on the surface of zinc granules. Zn + H2SO4 --> ZnSO4 + H2 => Pass the Hydrogen gas through the soap solution. Bubbles formed in the soap solution as Hydrogen gas it does not get dissolved in it

CBSE I NCERT 10th Numerical Problem solved Reflection and reflection of light

Q. 1. A concave mirror of focal length 20cm is placed 50 cm from a wall. How far from the wall an object be placed to form its real image on the wall? Solution: V= -50 cm F= -20cm From mirror formula 1/u = 1/f – 1/v = -1/20+ 1/50 = - 3/100 U = - 33.3 cm Therefore, the distance of the object from the wall x = 50 – u X = 50 – 33.3 = 16.7 cm. Q.2. An object is placed at a distance of 40cm from a concave mirror of focal length 15cm. If the object is displaced through a distance of 20 cm towards the mirror, By how much distance is the image displaced? Answer: Here f = - 15 cm, u = - 40 cm Now 1/f = 1/u + 1/v Then 1/v = 1/f – 1/u Or V= uf/u-f =( - 40 x -15)/25 = -24 cm Then object is displaced towards the mirror let u1 be the distance object from the Mirror in its new position. Then u1 = -(40-20) = -20cm If the image is formed at a distance u1 from the mirror then v1 = u1f/u1-f = -20X-15/-20+15 = -60 cm. = - 20 x-15/-20+15 = -60 cm. Therefor

Class 10 Metal and Non MetalsChapter 03 NCERT Activity Solutions

X Class 10 NCERT Activity Explanation Class 10 Metals and Non Metals Activity 3.1 Page No. 37 Take samples of iron, copper, aluminium and magnesium. Note the appearance of each sample. They have a shining surface. Clean the surface of each sample by rubbing them with sand paper and note their appearance again. They become more shiny. => Freshly cut Metal have shiny surface Activity 3.2 Page No. 37 Take small pieces of iron, copper, aluminium, and magnesium. Try to cut these metals with a sharp knife and note your observations. They are very hard to cut. Hold a piece of sodium metal with a pair of tongs and try to cut it with a knife. Sodium can be cut easily with knife. Hence K and Na are soft metal cut with knife Activity 3.3 Page No. 38 Take pieces of iron, zinc, lead and copper try to strike it four or five times with a hammer. These metals are beaten into thin sheet on hammering. This property of metal is called malleability and metals are called malleable. Activity 3.4 Page

Living science ratna sagar class 6 solutions

Ratna sagar living science 6 answers by jsunil. Class6 Living science solution Term-1 Living Science Solution chapter-1 Source of food Download File Living Science Solution chapter-2 Component of food Download File Living Science Solution chapter-3 Fibre to fabric Download File Living Science Sol ch-4 Sorting of material into group Download File Living Science Soln ch-5 Separation of substance Download File Living Science Solution chapter-6 Change around Us Download File Living Science Solution ch-7 Living and Non Living Download File Living Science Solution ch-8 Getting to Know Plants Download File Living Science Sol ch-9 The Body and Its movements Download File Visit given link for full answer Class6 Living science solution Term-II

Electricity numerical for class 10 CBSE Trend Setter 50 Problems

1. The current passing through a room heater has been halved. What will happen to the heat produced by it? 2. An electric iron of resistance 20 ohm draws a current of 5 amperes. Calculate the heat produced in 30 seconds. 3. An electric heater of resistance 8 ohm takes a current of 15 A from the mains supply line. Calculate the rate at which heat is developed in the heater. 4. A resistance of 40 ohms and one of 60 ohms are arranged in series across 220 volt supply. Find the heat in joules produced by this combination in half a minute. 5. A resistance of 25 ohm is connected to a 12 V battery. Calculate the heat energy in joules generated per minute. 6. 100 joules of heat is produced per second in a 4 ohm resistor. What is the potential difference across the resistor? 7. An electric iron is connected to the mains power supply of 220 V. When the electric iron is adjusted at minimum heating’ it consumes a power of 360 W but at ‘maximum heating’ it takes a power of 840 W. Ca