what is steric hinderance ?

Answer 1

I'm pretty shure it is or has 2 be a type of intermolecular force. preferably one that occurs when the size of groups inside a molecule slows down or stops the chemical reactions that happen in smaller related molecules.

Answer 2

Steric effects arise from the fact that each atom within a molecule occupies a certain amount of space. If atoms are brought too close together, there is an associated cost in energy due to overlapping electron clouds (Pauli or Born repulsion), and this may affect the molecule's preferred shape (conformation) and reactivity.

There are several types of steric effects:

Steric hindrance or steric resistance occurs when the size of groups within a molecule prevents chemical reactions that are observed in related smaller molecules. Although steric hindrance is sometimes a problem, it can also be a very useful tool, and is often exploited by chemists to change the reactivity pattern of a molecule by stopping unwanted side-reactions (steric protection). Steric hindrance between adjacent groups can also restrict torsional bond angles. However, hyperconjugation has been shown to be the correct explanation for the preference of the staggered conformation of ethane because the steric hindrance of the small hydrogen atom is far too small

Answer 3

The easy way to think of steric hindrance is to think of a triangle with a fence around it. If you hang bulky things on the fence they'll bump into each other. That costs energy. Nature likes to keep things as simple as possible and not put evergy out unless it has to. So it arranges things so that there is less interaction. Just remember size a Hydrogen is much smaller than a methyl group so there is less chance of them smacking into each other and won't cost as much as 2 methyl groups smacking into each other.

To make a long lecture short it's another way to describe conformation. It's the answer to everything for a sophmore organic student (doesn't make it wrong or right - but it's not the be all end all answer ie it's not a free pass to get the right answer). It helps direct reactions because when deciding attack points nature will go for the easy target that's less complicated.

Answer 4

my teacher said.... it is the physical obstacle, a particle have to overcome to come in contact with another particle in order to react.... or example.. in a box filled with soccer balls, and a tennis ball at the bottom. to reach the tennis ball u have to go through all the big balls, the less the easier.