HP Rolls Out New Printers, 3D Scanning, Better Cloud Printing. On Thursday, HP announced 13 new printers and scanners, many of which target the small and midsize business market. This new range of printers and scanners emphasizes Web-connected printing and advanced scanning. HP's TopShot Laserjet Pro M275 can scan 3D objects.
Typically, a single bond is a sigma bond while a multiple bond is composed of one sigma bond together with pi or other bonds. A double bond has one sigma plus one pi bond, and a triple bond has one sigma plus two pi bonds.
1 Note that ethene has 4 hydrogens attached to the double bond. 2  A monosubstituted alkene has 3, a disubstituted alkene has 2, a trisubstituted alkene has 1, and a tetrasubstituted alkene as none. 3  Please note, also, that the nature of the alkyl group makes no difference. Hence the pi bond is weaker than the sigma bond, easier to break, making alkenes much more reactive than alkanes. 2  You should know that the pi bond strength is ca. 63 kcal/mol, and that the pi bond is completely broken by a relative rotation of 90 degrees.