Question

1. How do you calculate the electronegativity of an atom or molecule?

2. Explain the intermolecular and intramolecular forces.

3. How can I determine/classify the type of intermolecular force by its structural formula?

4. How can I tell if a substance has a smell or does not have a smell by its structural formula?

*PLEASE GIVE THOROUGH EXPLANATIONS, I AM VERY LOST IN MY CHEMISTRY CLASS RIGHT NOW*

Answer 1

Answer 1:- Electronegativity is defined as the ability of an atom in a molecule to polarized electrons density towards itself.

Three clear and easy ways to calculate electronegativity of any atom or molecule.

1 Understand that chemical bonds occur when atoms share .

2 Understand how electronegativity affects the electrons in the bond.

3 Use an electronegativity table as a reference.

4 Remember electronegativity trends for easy estimations.

Let us take a example to understand how we can find the electronegativity of atom-

Find the electronegativity difference between the two atoms. When two atoms are bonded together, the difference between their electronegativities can tell you about the qualities of their bond. Subtract the smaller electronegativity from the larger one to find the difference.

For example, if we're looking at the molecule HF, we would subtract the electronegativity of hydrogen (2.1) from fluorine (4.0). 4.0 - 2.1 = 1.9.

Answer 4 : -

the smell of many substances comes from a combination of many molecules. Moreover small changes in molecules can make an amazing difference to their    smell.

Simple alkylpyrazines like 2,3-dimethylpyrazine (1) and 2,6-dimethylpyrazine (2) are responsible for the nutty smells of roasted peanuts and baked bread; just a small tweak, and 2-ethyl-3,5-dimethylpyrazine (3) is one of the 'chocolate' molecules that rounds out the roasted smell of coffee. Substituting slightly different groups to give 2-isobutyl-3-methoxypyrazine (4) gives green bell peppers their distinctive smell, which can be detected as low as 0.002 parts per billion; and 2-acetylpyrazine (5) smells of roasted popcorn.