Given :
Number of He atoms, 
atoms.
To Find :
How many grams are their in given number of He atoms.
Solution :
We know, molecular mass of He is 4 g. It means that their are 
atoms in 4 g of He.
Let, number of gram He in 
atoms is x , so :
Therefore, grams of He atoms is 22.58 g .
Scirnce uses a method of testing to declare rules or facts. myth and fairy tales have no way of being tested. cats are a physical creature we can see, test, and observe. a mythical idea canny be tested. for example: mermaids cannot be tested as we have none to observe.
Answer:
helium , krypton,xenon,radon, argon are noble gasses
