3.00 L of Ch4 is known to contain 0.650 moles at a certain temperature and pressure if the volume of a chamber of CH4 increased from 7.00L to 8.20 L how many moles CH4 were added assume temperature and pressure stayed constant

0.111 moles of were added

Explanation:

According to the Avogadro's law, the volume of gas is directly proportional to the number of moles of gas at same pressure and temperature. That means,

or,

where,

= initial volume of gas  = 7.00 L

= final volume of gas = 8.20 L

= initial moles of gas  = 0.650 mole

= final moles of gas  = ?

Now we put all the given values in this formula, we get

Thus moles added are (0.761-0.650) = 0.111 moles