Download question bank acids, bases and salts

GITARATTAN JINDAL PUBLIC SCHOOL
ROHINI DELHI-110085
QUESTION BANK
CLASS
: VII
SUBJECT : SCIENCE
ACIDS, BASES AND SALTS
MULTIPLE CHOICE QUESTION ( 1 MARKS EACH)
1. An indicator is a substance which shows the presence of a chemical substance by:
i. giving odour
ii. Changing colour iii. Producing sound iv. All of these
2. The two kinds of litmus paper are:
i. blue and yellow ii. Yellow and red iii. Blue and red iv. All of these
3. In acids, methyl orange turns:
i. green ii. Yellow iii. Red iv. White
4. in bases, methyl orange turns:
i. green
ii. Red
iii. Yellow iv. Black
5. Phenolphthalein changes to which colour in an acidic medium.
i. Pink
ii. Blue
iii. Green
iv. Black
6. In bases, phenolphthalein turns:
i. colourless
ii. Pink
iii. Red
iv green
7. Antacids contain:
i. weak base
ii. Weak acid
iii. Strong base
iv. Strong acid
VERY SHORT ANSWER TYPE QUESTIONS (1 MARKS EACH)
1. What happens when an acid reacts with a metal ?
2. Name two bases ?
3. Name two mineral acids ?
4. To which colour does turmeric change in the presence of an alkali ?
5. Name two indicator?
6. Name the acid present in Lemmon juices?
7. What is the other name of lime? 8. Which gas is used in fire extinguishers?
9. Which acid is called the king of chemical?
10. Give one used of milk of magnesia?
SHORT ANSWER TYPE QUESTIONS (2 MARKS EACH)
1. State differences between acids and bases.
2. Name the source from which litmus solution is obtained. What is the use of this solution?
3. Explain why: An antacid tablet is taken when you suffer from acidity.
4. Explain why: Factory waste is neutralized before disposing it into the water bodies.
5. What are Indicators Give two examples?
6. What is an oxide?
7. What are mineral acid?
8. What do you mean by concatenated and dilute acid?
9. Why mineral acid dangers?
10. How would you prepare crystal of copper sulphate from?
ANSWER THESE QUESTIONS (3 MARKS EACH)
1. Blue litmus paper is dipped in a solution. It remains blue. What is the nature of the solution?
Explain.
2. List the properties of acids ?
3. How can the effect of china rose on acids and bases be seem ?
4. What happens when a concentrated acid gets accidentally spilled on cloth or wool ?
5. What happen when metals and non metals combined with oxygen, also write chemical equation ?
LONG ANSWER TYPE QUESTIONS (5 MARKS EACH)
1. Is the distilled water acidic/basic/neutral? How would you verify it?
2. Describe the process of neutralization with the help of an example.
3. Three liquids are given to you. One is hydrochloric acid, another is sodium hydroxide and third
is a sugar How will you identify them? You have only turmeric indicator.
4. How neutralization reaction is useful in soil treatment and in indigestion.
5. What is a base? Write two uses of the following magnesia ?
1. Slaked lime 2. Milk of Magnesia
FILL IN THE BLANKS (1 MARKS EACH)
1. Metals combine with oxygen to form………………………oxides.
2. Soluble bases are called………………………………………
3. A base reacts with an acid to form………………………………and………………………..
4. Alkali are……………………………….in touch.
5. ……………………………………….acid is an exception which is a mineral acid but does not react with
metals.
6. In an acidic medium litmus turns………………………….in color.
7. A base is a natural dye as it is extracted from the plant……………………………….
8. Alcohol, oxygen and petrol are examples of …………………………………substances.
9. All acids contain…………………………………………..
10. Acids turns blue litmus………………… Bases turn red litmus……………………….