The carbon dioxide molecule is linear. The electronegativities of C and O are 2.5 and 3.5, respectively. Based on these values and on consideration of molecular geometry, the C-O bond is and the molecule is .

polar,non polar

Explanation:

The electronegativity of C is 2.5 and of O is 3.5 .The difference in electronegativity(3.5-2.5=1.0) is 1.0 and as per rule if the difference in electronegativity of atoms in a bond is >0.4 then the bond is considered polar. So in this case C-O bond is polar.

However, the symmetrical arrangement of the bonds in the molecule of CO2 makes its non polar.The CO2 molecule is linear so the C-O dipole moment on either side will cancel out each other hence the net dipole moment will be zero.

altitude, density, pressure

air gets less dense the higher the altitude and also the air pressure is less as altitude rises.