In pent− 2 −yne (CH₃CCCH₂CH₃), there are four atoms in a straight line. Use dashed lines and wedges to draw three-dimensional representation of this molecule, and circle the four atoms that are in a straight line.

To draw a molecule on a piece of paper, dashed wedges are used to bond the atoms that are projecting away from us, and full wedges are used to bond the atoms that are projecting towards us. Solid lines are used to bond the atoms that are in the plane of paper.

The mixing of atomic orbitals to give equal number of symmetrically hybridized orbitals is known as hybridization. The different types of hybridization are sp , sp² , sp³ , sp³d , sp³d² or sp²d³ , sp³d³ . sp hybridization is linear with a bond angle of 180° , sp² hybridization is trigonal planar with a bond angle of 120° and sp³ hybridization is tetrahedral with a bond angle of 109.5°

The atoms on the triple bond are hybridized and the molecule is linear in shape with a bond angle of 180° .