A cylinder with a moveable piston contains 0.90 mol of gas and has a volume of 339 mL.?

Supposing the temperature and pressure remain constant:

(339 mL) x (0.90 + 0.21) / (0.90) = 418 mL

Avogadro's regulation states that equivalent volumes of gasses on the comparable temperature and rigidity would desire to comprise equivalent variety of molecules. In 0.ninety 3 mol, you have 5.60046 x 10^23 molecules. So 5.60046 x 10^23 molecules occupy 349 mL of quantity. and each 1mL would desire to comprise a million.6047 x 10^21 molecules. you have an entire of 0.ninety 3 + 0.19 mol = a million.12 mol. meaning you have 6.7446 x 10^23 molecules. quantity = 6.7446 x 10^23/a million.6047 x 10^21 = 420.305....mL In 2 sig. fig. = 420 mL.