<P> A typical double bond consists of one sigma bond and one pi bond ; for example , the C = C double bond in ethylene . A typical triple bond , for example in acetylene , consists of one sigma bond and two pi bonds in two mutually perpendicular planes containing the bond axis . Two pi bonds are the maximum that can exist between a given pair of atoms . Quadruple bonds are extremely rare and can be formed only between transition metal atoms , and consist of one sigma bond , two pi bonds and one delta bond . </P>
<P> A typical double bond consists of one sigma bond and one pi bond ; for example , the C = C double bond in ethylene . A typical triple bond , for example in acetylene , consists of one sigma bond and two pi bonds in two mutually perpendicular planes containing the bond axis . Two pi bonds are the maximum that can exist between a given pair of atoms . Quadruple bonds are extremely rare and can be formed only between transition metal atoms , and consist of one sigma bond , two pi bonds and one delta bond . </P>
number of pi bonds in a triple bond
number of pi bonds in a triple bond
two
two