How many moles are present in 205 g of helium? With steps and explanation

51.2mol

Step-by-step explanation:

molar mass of helium is 4.003g/mol

mole= mass/molar mass

= 205/4.003

= 51.2mol

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation:

step-by-step explanation:

circumference divided by 3.141592654 then timesthe radius twice