Identify the substance that evaporates at room temperature:
Water
Oil
Kerosene
Ammonium chloride
Which of the following is the easiest to change?
The colour of your hair
The shape of your face
The colour of your eyes
Both A & C
A seed growing into a tree is an example of:
Slow physical change
Fast periodic change
Slow natural change
Man made reversible change
In an endothermic reaction:
Energy is released
Energy is absorbed
Energy is neither released nor absorbed
Energy is not required
A chemical reaction in which energy is liberated is called:
Exothermic reaction
Physical change
Endothermic reaction
Photo chemical reaction
When liquids are heated, they turn into gases. The yellow egg yolk present inside the egg is a liquid but when it is heated, it changes into an omelet which is solid, why?
Sometimes, liquids turn into solids
Omelet does not follow the above rule
Strictly speaking, the rule does not apply to complex mixtures and egg yolk is a complex mixture
None
Which of the following is a feature of physical change?
It is reversible
It is temporary
No new substance is formed
All of these
Melting of ice is an example of:
Chemical combination
Chemical decomposition
Dissolving salt in water is a/an:
Endothermic change
Exothermic change
Both A and B
Rusting of iron is a chemical change because:
It can be cleaned and the original substance recovered
It is a slow reaction
A new substance is formed
