Structure of Molecules

Question 1

what is valence electronic configuration of inert gases?

Answer 1

ns2np6

Question 2

why do inert gases do not participate in reactions?

Answer 2

they are stable

Question 3

in forming compounds, atom tend to gain electronic configuration like ____________.

Answer 3

noble gas

Question 4

what is octet rule?

Question 5

what is duplet rule?

Question 6

what is ionic bond?

Answer 6

An ionic bond is a type of chemical bond formed when one atom transfers electrons to another atom. The atom that loses electrons becomes a positively charged ion, called a cation. The atom that gains electrons becomes a negatively charged ion, called an anion. The oppositely charged ions are attracted to each other by electrostatic forces, which holds the ionic bond together.

Question 7

what are ionic compounds?

Answer 7

ionic compounds consist of ions formed from the transfer of electrons between metals and non-metals and joined by electrostatic forces.

Question 8

ionic compounds have _____ boiling points.

Answer 8

high

Question 9

what are covalent bonds?

Answer 9

a chemical bond that involves the sharing of e- to form e- pairs b/w atoms.

Question 10

what is double covalent bond?

Answer 10

bonds that are formed by sharing two electron pairs.

Question 11

what are lone pairs?

Answer 11

pairs of valence electrons which are not shared between atoms.

Question 12

draw electron dot & cross structure for the formation of Na & Cl Mg & F

Answer 12

67

Question 13

ionic compounds are physically _______________ & have __________ melting points.

Answer 13

crystalline solids
high

Question 14

name all periodic properties?

Answer 14

SAIEE
South African Institute of Electrical Engineers.

Question 15

non-metals tend to form anions. why?

Answer 15

cz they have high ionization energies.

Question 16

draw electron dot & cross structure for the formation of CH4 & N2

Answer 16

70

Question 17

draw electron dot & cross structure for the formation of Na ion & F ion

Answer 17

65 & 66

Question 18

draw electron dot & cross structure for the formation of F and O covalent bond?

Answer 18

69

Question 19

draw electron dot & cross structure for the formation of the following molecules:
HCN
CO2

Answer 19

71
hydrogen cyanide

Question 20

a covalent bond can only occur between two similar atoms.
F/T

Answer 20

F
a covalent bond can occur between two similar and unlike atoms.

Question 21

what are non-polar covalent compounds?

Answer 21

when two identical atoms share electron pairs, both the atoms exert same force on the shared pairs.

Question 22

in polar or non-polar covalent bond, which atom will attract electrons the most?

Answer 22

the one with high electronegativity.

Question 23

what is polar covalent bond

Answer 23

the electrons are shared unequally, as one atom exerts a stronger force of attraction on the electrons than the other.

The ability of an atom to attract a pair of electrons in a chemical bond is called its electronegativity.

Question 24

electron density?

Answer 24

the probability of finding an electron within a specific region of space around an atom or within a molecule.

Question 25

what is hydrogen bond?

Answer 25

the interaction of a highly electron deficient hydrogen and lone pair on a nearby highly electronegative atom such as N, O or F.

electron-deficient: fewer electrons in valence shell.

lone pair atoms are highly electronegative.
Hydrogen bonding is a special type of dipole-dipole attraction.

Question 26

hydrogen bonding is/is not chemical bond.

Answer 26

is not
it’s just a force.

Question 27

intermolecular meaning?
intramolecular meaning?

Answer 27

inter = between (molecules)
intra = within (atoms in molecules)

Question 28

what is an intermolecular force?

Answer 28

attractive force between molecules

Question 29

how many types of covalent bonds?

Answer 29

2
polar
non-polar

Question 30

what are adhesives?

Answer 30

Adhesives are substances that are used to bond two or more surfaces together by creating a strong and durable connection

glue

Question 31

why metals have high melting and boiling point?

Answer 31

The atoms in metals are closely packed. So, they need more energy to move them apart and convert them into liquid.

Question 32

why covalent compounds cannot conduct electricity?

Answer 32

the molecules are neutral and there are no charged particles (no ions or electrons) to move and carry charge.

Question 33

why ionic compounds conduct electricity in molten state?

Answer 33

they contain charged particles called cations and anions. These ions are free to move to conduct electricity.

Question 34

dipole dipole hydrogen bond are a type of _________.

Answer 34

intermolecular forces