No student devices needed. Know more
10 questions
What change will happen to the slices of potato if they will be exposed to oxygen in the air?
Color will change from brown to white
Color will change from white to brown
The color will not change
No changes in color
2. What causes the rusting of iron nails or iron made materials in a wet cloth?
presence of heat
absence of heat
presence of oxygen
absence of oxygen
When the candle was lighted, it melted into liquid and became solid again after few seconds or in a minute. What causes these changes?
I. presence of heat II. presence of oxygen
III. absence of heat IV. absence of oxygen
I, II and III
I and IV
I and II
All of the above
4. The candles melted by the application of heat. What change took place when solid candles became liquid?
chemical
mechanical
no change
physical
5. Which situation shows the presence of oxygen in a material?
I. Lighting of a candle III. Combustion of engines
II. burning of fuels IV. putting off a lighted candle
I, II and III
I and IV
I and II
All of the above
6. The eggplant/apple in the experiment turned its color from white to brownish. Which statement is NOT TRUE?
The presence of oxygen caused change in its color.
The absence of oxygen caused change in its color.
The color of an apple/eggplant changed when it is exposed to
oxygen in the air.
There is oxidation that happened when apple/eggplant was sliced and exposed in the air.
Water is the primary cause of rust because water contains _____?
Oxygen
Chloride
carbon
hydrogen
8. Joram noticed that when he mopped the floor using wet rugs, the moist in the floor disappeared after few minutes. What is the reason why the floor became dry?
presence of heat
absence of heat
presence of water
absence of temperature
9. When physical change in materials happened, there is__________.
I. formation of new product or material
II. no formation of new product or material
III. formation of new shape
IV. formation of new color
I, III and IV
II only
III and IV
II and III
10. Hannah observed that the left over foods on the table became watery, spoiled and had foul odor after 48 hours. What caused this change in the material?
I. presence of heat III. presence of oxygen
II. absence of heat IV. absence of oxygen
I and II
II and III
I and III
II and IV
Explore all questions with a free account