Rotation about a carbon-carbon double bond does not readily occur because: .1) the overlap of the p orbitals of the carbon-carbon π bond would be lost2) the double bond is much shorter and therefore more difficult to rotate3) the overlap of the sp2 orbitals of the carbon-carbon σ bond would be lost4) the double bond is much stronger and therefore more difficult to rotate

1) The overlap of the p orbitals of the carbon-carbon π bond would be lost

Explanation:

Unlike simple bonds, a double bond can not rotate, since it is not possible to twist the ends of the molecule without breaking the π bond.

In the structure of but-2-ene present in the attachment, we can see the two isomers, cis and trans. These isomers cannot be interconverted by rotation around the carbon-carbon double bond without breaking the π bond.

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.