Answer: To show the number of atoms present.
Explanation: As in CO² (Carbon dioxide), there is a small 2 next to the symbol "O" (oxygen) to explain that there are two oxygen atoms.
there are 4.0 moles of SO3
Answer:
when cell is exposed to radiation we get brain tumour or cancer.
Answer:
Ammonium nitrate, (NH4NO3), a salt of ammonia and nitric acid, used widely in fertilizers and explosives. The commercial grade contains about 33.5 percent nitrogen, all of which is in forms utilizable by plants; it is the most common nitrogenous component of artificial fertilizers.
Helium is a chemical element of the atomic number 2, an inert gas that is the lightest member of the noble gas series.
These means, Helium is lighter than air, and for this is why all other balloons may not float.
The helium balloon displaces an amount of air (Just like an empty water bottle displaces an amount of water). As long as the weight of the helium plus the balloon fabric is lighter than the air displaces, the balloon will float in the air.