MODEL ACTIVITY TASKS
ENVIRONMENT AND SCIENCE
What is the smallest particle of an element ? Write the formula of an oxygen molecule.
Why are small pores found on the surface of a bread ?
There are three hydrogen atoms and a nitrogen atom in a molecule of ammonia. Mention the
formula of ammonia and determine the valency of the nitrogen atom in it.
Once they dissolve in water, grains of sugar are no longer visible to the naked eye. What
experiments can be performed to prove the existence of sugar molecules in the solution ?
CLASS - VI
Write the answers to the questions given below:
1.
2.
3.
4.
How do red ants and squirrels depend on plants?
5.
6.
Explain why azolla is grown in paddy fields.
Answers
Answer:
Explanation:
1 ATOM
2 When the dough is baked in the oven , the gaseous bubbles burst resulting in small pores inside the bread . When this mixture is added to dough and it is baked , carbon dioxide is produced . The bubbles of the gas break up on baking causing small pores.
3.An example of covalent compound is ammonia . The chemical formulae of ammonia is NH3 start subscript , end subscript , which tells us that in a single molecule of ammonia , there is one nitrogen and three hydrogen atoms.
4. They depends on plants as squirrel eat nuts from the plants and red ants depends on plants because they live in some houses and they eat sweet things such as sugar which comes from the sugarcane and it’s a plant.
5.When sugar dissolved in water it is not visible as the sugar particles have filled the spaces between the water particles.
As intramolecular forces in liquids are lesser than solids so sugar particles get in the spaces between water molecules.
6. Rice farmers keep Azolla pinnata in the rice field in their paddies because it generates valuable nitrogen via its symbiotic cyanobacteria.T his plant can be grown in wet soil and then plowed under, generating a good amount of nitrogen-rich fertilizer.