The answer is 0 if im right
P1V1 = P2V2
P1 = 720 mmHg
V1 = 450. mL
P2 = 760 mmHg (this is the pressure at STP)
Use these to solve for V2:
(720)(450) = 760V2
V2 = 426 mL
Answer:
300,000km is the speed of light
Answer is: Allena is correct. It is an element because it is only made of chlorine atoms.
A chemical element bonded to an identical chemical element is not a chemical compound since it is made from only one element and not from two different elements. Chlorine is molecule, but not compound.