The germination of a seed is:
A physical, reversible change in which energy is produced
A fast, chemical reaction in which energy is released
A slow, irreversible, desirable, chemical change
A fast, irreversible, undesirable chemical change
Cloud seeding is a technique used to induce rain that was first used by USA in 1946. It has also been done in Karnataka and other places in India. What is it ?
An agricultural practice that depends on clouds
Introduction of particles in clouds to increase condensation
Making clouds and placed them in the sky
Trimming the clouds into seed like structures
A seed growing into a tree is an example of
Slow physical change
Fast periodic change
Slow natural change
Man made reversible change
The characteristics of a good fuel are
It should release more energy
It should be safe
It should be easily transportable
All of the above
Rate of the reaction depends on:
Temperature
Concentration of the reactants
Presence of catalyst
All the above
Burning of a match stick is a/an
Endothermic reaction
Exothermic reaction
Chemical change
Both B & C
Dissolving salt in water is a/an
Endothermic change
Exothermic change
Both A and B
Chemical combination
A substance which alters the rate of reaction:
Reactant
Product
Ingredient
Catalyst
In our body, ______ acts as catalysts
Vitamins
Minerals
Enzymes
Water
When you burn petrol,flames are produced. This is a/an
Physical change
Reversible reaction
