In this page we have Worksheet for Class 7 Science Chapter 4: Acid Base and Salt . Hope you like them and do not forget to like , social share
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Question 1
Fill in the blanks
(a) The most commonly used natural indicator is__________________________and is extracted from______________________________
(b) Aqueous solution of baking soda is bitter in taste and feels soapy on touching because it contains______________________________
(c) __________________are used to test whether a substance is acidic or basic in nature.
(d) ____________________change their colour when added to a solution containing an acidic or basic substance.
(e) Lemon juice, orange juice taste sour because they contain_______________________
(f) The solutions which do not change the colour of either blue or red litmus are called ____________________solutions.
(g) Turmeric and litmus are _________ acid-base indicators..
(h) In neutralization reaction heat is always___________________________________.
(i) Salts may be____________________________or_____________________in nature.
(j) Chemically milk of magnesia is______________and baking soda is_______________
(k) China rose indicator turns__________________________solution to dark pink and______________________solution to green
(l) The correct way of making a solution of acid in water is to _________
Answer
(a) litmus, lichens
(b) Base
(c) Indicator
(d) Indicator
(e) Acid
(f) Neutral
(g) Natural
(h) produced or evolved
(i) acidic,basic or neutral
(j) Magnesium hydroxide,Sodium bicarbonate
(k) acidic, basic
(l) add acid to water.
Multiple Choice Questions
Question 2
Sodium bicarbonate is commonly called
(a) Lime water
(b) Slaked lime
(c) Washing soda
(d) Baking soda
Question 3
Which of the following statements is correct?
(a) Indicator is a substance that shows different colors in acidic and basic solution.
(b) Turmeric stain on a white shut turns to red when it is washed with soap.
(c) Lime water is a solution of calcium hydroxide.
(d) All the above are correct.
Question 4 >
Neutralisation reaction is a
(a) physical and reversible change.
(b) physical change that cannot be reversed.
(c) chemical and reversible change.
(d) chemical change that cannot be reversed
Question 5
Which of the following is an acid-base indicator?
(a) Vinegar
(b) Lime water
(c) Turmeric
(d) Baking soda
Question 6
'Litmus', a natural dye is an extract of which of the following?
(a) China rose (Gudhal)
(b) Beetroot
(c) Lichen
(d) Blue berries (Jamun)
Question 7
Which medicines are used for treating indigestion?
(a) Antibiotic
(b) Analgesic
(c) Antacids
(d) Antiseptic
Answer
2. (d)
3. (d)
4. (d)
5. (c)
6. (c)
7. (c)
Very Short Answer type
Question 8
Provide the chemical Name of below acid or base
(a) Vinegar
(b) Fruits (orange)
(c) Curd
(d) Lime water
(e) Window cleaner
(f) Soap
Question 9
What is the colour change for below indicator for Acid and Bases
(a) Blue litmus
(b) Red litmus
(c) Phenolphthalein
(d) Turmeric
Answer
(a) Acid : Turns Red ,Base : No change
(b) Acid : No change ,Base : Turns Blue
(c) Acid : Colurless, Base: pink color
(d) Acid: No change, Base : change to red
Short Answer type
Question 10
Give a reason why
(a) Great care should be taken while handling laboratory acids and bases.
(b) Solid powder of baking soda does not turn dry litmus paper to blue in color.
Question 11
Define acid rain and how it is produced? What are its harmful effect?
Question 12
Define neutralization reaction with an example. List its 3 applications.
Question 13
You are provided with four test tubes containing sugar solution, baking soda solution, tamarind solution, salt solution. Write down an activity to find the nature (acidic/basic/neutral) of each solution. Also Read
