So, let's look at an example of equilibrium in the cookie market and see what happens when things change. Let's say the equilibrium price for a chocolate chip cookie is $3. Here's an example of the supply and demand curves, with an equilibrium price of $3, which is at the intersection of the supply and demand curves.
A sigma bond is the end-to-end overlap of the bonding orbitals, usually hybrid orbitals. The sigma bond is a single bond. A pi bond is the side-to-side overlap of unhybridized p-orbitals. A pi bond, along with a sigma bond form a double bond. A triple bond is two pi bonds and a sigma bond. Take a look at this diagram showing a sigma bond and a pi bond, forming a single bond and a double bond. http://metafysica.nl/ethylene01.jpg.
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.