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question_answer1)
Raveena covered a beaker of boiled water with a metal tray as shown in the diagram.
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The beaker and metal tray were then removed from the tripod stand and left on the table. After two minutes, which of the following can be observed?
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A)
Water droplets are seen on the outer part of metal tray. done
clear
B)
Water droplets are seen on the inner part of tray and inner part of the beaker. done
clear
C)
Water droplets are seen on the inner part of metal tray and outer part of the beaker. done
clear
D)
Water droplets are seen on the outer part of beaker only. done
clear
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question_answer2)
Sudha took lemon juice in two flasks. She put salt in flask I and washing soda in flask II. She observed lots of bubbles in flask II but nothing in flask I. What could be the reason for this?
A)
In flask I, a chemical change takes place. done
clear
B)
In flask II, a chemical change takes place and bubbles of carbon dioxide are seen. done
clear
C)
In flask II, a physical change takes place producing lots of bubbles. done
clear
D)
In flask I, salt reacts with lemon juice and forms a new compound. done
clear
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question_answer3)
Study the given Venn diagram carefully.
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The centre point X represents
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A)
Burning of paper done
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B)
Dissolving salt in water done
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C)
Boiling of an egg done
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D)
Bursting of a balloon. done
clear
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question_answer4)
A metallic piece (X) is dropped into copper sulphate solution. After some time, the blue colour of the solution changes to green. The change which has occurred is
A)
Physical and reversible change done
clear
B)
Physical and irreversible change done
clear
C)
Chemical and reversible change done
clear
D)
Chemical and irreversible change. done
clear
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question_answer5)
Read the given passage and fill in the blanks by choosing an appropriate option. Iron nails when new are grey and bright. When exposed to ___(i)___, they get covered with a ___(ii)___ coating. This process is called ___(iii)___ and it is a ___(iv)___ change.
A)
B)
C)
D)
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question_answer6)
Mark the incorrect statement.
A)
Melting of wax is a physical change while burning of wax in a candle is a chemical change. done
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B)
Metals expand on heating while contract on cooling. Both are physical changes. done
clear
C)
Composition of matter changes during a chemical change while it remains same during a physical change. done
clear
D)
High and low tides in sea are the examples of non-periodic changes while growth of a tree is a periodic change. done
clear
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question_answer7)
Few changes are given below. Mark the correct option from the codes given below.
(i) Milk is set to form curd. |
(ii) Batter is steamed to form idlis. |
(iii) Water is boiled to form steam. |
(iv) Salt is dissolved in water to form solution. |
A)
B)
C)
D)
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question_answer8)
Nitu mixed some iron filings with sulphur powder in a China dish. She heated the contents of China dish. What did she observe during the experiment?
A)
There was no difference in the contents of China dish before and after heating. done
clear
B)
Before heating, iron filings and sulphur powder could be seen separately but after heating the content became black. done
clear
C)
Before heating, the iron filings and sulphur powder could not be seen separately. done
clear
D)
Before heating, the contents were black and after heating, iron filings and sulphur could be seen separately. done
clear
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question_answer9)
What is common among the following phenomena?
1. Blinking of traffic lights. |
2. Rotation of blades of a fan. |
3. Swinging of pendulum of a clock. |
A)
All are chemical changes. done
clear
B)
All are periodic changes. done
clear
C)
All are undesirable changes. done
clear
D)
All are irreversible changes. done
clear
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question_answer10)
Observe the two figures given below. In figure I, a solution of sugar in water is heated and in figure II, only sugar is being heated. What is the correct sequence of changes taking place?
A)
In figure I, physical change is taking place while in figure II a chemical change is taking place. done
clear
B)
In figure I, a chemical change is taking place while in figure II a physical change is taking place. done
clear
C)
In both figures, physical changes are taking place. done
clear
D)
In both figures, chemical changes are taking place. done
clear
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question_answer11)
Rohan tore a sheet of paper into pieces and then burnt them. Identify the irreversible change taking place in the process.
A)
Tearing the sheet into pieces. done
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B)
Burning the pieces done
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C)
Both tearing and burning the pieces done
clear
D)
None of these. done
clear
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question_answer12)
Study the flowchart carefully.
(i) Melting of ice
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(i) Cutting of paper
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(ii) Blowing of balloon
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(ii) Flowering of bud Which of the following is correct?
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A)
B)
C)
D)
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question_answer13)
A potter shapes pots out of clay (Process 1). He then bakes the pots in an oven (Process 2). Which of the following statements is correct?
A)
Process 1 is a reversible, physical change while process 2 is an irreversible, physical change. done
clear
B)
Process 1 is an irreversible, physical change while process 2 is an irreversible, chemical change. done
clear
C)
Process 1 is a reversible, physical change while process 2 is an irreversible, chemical change. done
clear
D)
None of these. done
clear
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question_answer14)
Match the column I with column II and choose the correct option from the codes given below:
Column I | Column II |
P. Digestion of food in our body | (i) Fast change |
Q. Earthquake | (ii) Natural, desirable change |
R. Falling of stone | (iii) Natural, undesirable change |
S. Change of seasons | (iv) Slow change |
A)
P-(iv), Q-(ii), R-(iii), S-(i) done
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B)
P-(iii), Q-(iv), R-(ii), S-(i) done
clear
C)
P-(ii), Q-(i), R-(iv), S-(iii) done
clear
D)
P-(iv), Q-(iii), R-(i), S-(ii) done
clear
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question_answer15)
Consider the following phenomena:
(i) Forest fire |
(ii) Growth of plants |
(iii) Low and high tides |
(iv) Occurrence of a rainbow |
(v) Earthquakes |
(vi) Opening of a morning glory flower. |
Which of the above phenomena can be classified as periodic changes?
A)
(i), (ii) and (iii) done
clear
B)
(i), (ii) and (v) done
clear
C)
(iv), (v) and (vi) done
clear
D)
(iii) and (vi) done
clear
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question_answer16)
Observe the given figure carefully and choose the correct statement,
A)
Processes (iii) and (iv) involve absorption of heat energy. done
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B)
Process (v) involves condensation and freezing. done
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C)
Processes (i) and (iii) evolve heat energy. done
clear
D)
Process (v) absorbs a lot of heat energy. done
clear
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question_answer17)
Swati classified a few changes occurring around us as shown in the table.
No. | Changes | Type |
1. | Sharpening of pencil | Physical, reversible |
2. | Evaporation of water | Physical, irreversible |
3. | Opening of a bud | Chemical irreversible |
4. | Rusting of iron | Chemical reversible |
Which of the changes is/are classified correctly?
A)
2 and 3 only done
clear
B)
3 and 4 only done
clear
C)
1 and 4 only done
clear
D)
3 only done
clear
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question_answer18)
Read the given statements and mark the correct option.
Statement 1: While fixing a metal rim on a wooden wheel of a cart, the size of the metal rim is kept slightly smaller than that of the wooden wheel. |
Statement 2: Metals expand on heating and contract on cooling. |
A)
Both statements 1 and 2 are true and statement 2 is the correct explanation of statement 1. done
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B)
Both statements 1 and 2 are true but statement 2 is not the correct explanation of statement 1. done
clear
C)
Statement 1 is true and statement 2 is false. done
clear
D)
Both statements 1 and 2 are false. done
clear
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question_answer19)
Study the given Venn diagram.
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Identify points 1, 2 and 3.
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A)
B)
C)
D)
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question_answer20)
Observe the given processes 1 and 2 carefully.
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Which of the following statements are correct?
I. Bubbles are formed in process 1 while no bubble formation takes place in process 2. |
II. Process 1 is slow while process 2 is fast. |
III. Process 1 occurs at \[{{100}^{o}}C\]only while process 2 can occur at any temperature. |
A)
I and II only done
clear
B)
II and III only done
clear
C)
I and III only done
clear
D)
All of these. done
clear
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