Small children are occasionally injured when they try to inhale helium from

a compressed helium tank. If a small child tries to transfer the contents of

a 50 L tank of helium at a pressure of 125 atm and a temperature of 20°

C into its lungs, how many moles of gas will it inhale?

260 moles of Helium

Explanation:

V = 50L

T = 20°C = (20 + 273.15)K = 293.15K

P = 125 atm

R = 0.082 L.atm / mol. K

n = ?

From ideal gas equation,

PV = nRT

P = pressure of a given gas

V = volume it occupies

n = number of moles

R = ideal gas constant

T = temperature of the gas

PV = nRT

n = PV / RT

n = (125 * 50) / (0.082 * 293.15)

n = 6250 / 24.0383

n = 260.00 moles

The child inhaled 260 moles of Helium

2h2o2--> 2h2o + o2

this reaction is of the spontaneous decomposition of hydrogen peroxide down into water and oxygen.

add 2 molecules of hydrogen peroxide and 2 molecules of water. since oxygen is naturally diatomic, the total number of atoms of each element is now the same on both sides of the equation so it is balanced.

this may not be entirely correct but let me know.

there are two significant figures.