Electrons, Bonding and structure module 2.2

Question 1

ionic bonding

Answer 1

electrostatic attraction between positive and negative ions

Question 2

explain the solid structure of giant ionic lattices

Answer 2

the oppositely charged ions surrounding each ion attracts each other from all directions forming a giant ionic lattice

Question 3

explain why ionic compound have a high melting and boiling point

Answer 3

because a large amount of energy is needed to break the strong electrostatic bonds that hold the oppositely charged ions in the giant lattice.

Question 4

why does MgO have a higher melting point than NaCL?

Answer 4

Because Mgo has a greater charge and the greater the charge the stronger the electrostatic forces between the ions.

Question 5

explain the conductivity of a ionic compound in solid and molten state

Answer 5

in a solid the ions are held in a fixed position and no ions can move so they can’t carry the electrical current therefore it does not conduct electricity. When molten the ions are free to move so can conduct electricity.

Question 6

describe the solubility of ionic compounds?

Answer 6

they dissolve is polar solvents as they break down the ionic lattice by surrounding each ion. the slight charges within the polar substances attract to the charged ions in the giant ionic lattice meaning the structure is disrupted and ions are pulled out of it

Question 7

why does solubility decrease as the charges of the ions increases

Answer 7

the polar substance cannot overcome tthe electrostatic forces of attraction

Question 8

covalent bonding

Answer 8

the strong electrostatic attraction between shared pair of electrons and the nuclei of the bonded atom

Question 9

why are some elements able to have 10 electrons in there outer shell when they form a covalent bond?

Answer 9

because they have a 3d subshell so are able to have a maximum of 18 in there outer shell. this is called expansion of the octect

Question 10

average bond empathy

Answer 10

a measurement of covalent bond strength

Question 11

CH4 angle

Answer 11

109.5

Question 12

NH3 angle

Answer 12

107

Question 13

H20 angle

Answer 13

104.5

Question 14

Factors electronegativity depends on

Answer 14

• the size of the positive charge on the nucleus. The more protons in the nucleus the higher the charge
• the atomic radius, the smaller the atomic radius the closer the bonding electrons will be be to the nucleus of an atom so the more electronegativity
• shielding of the nucleus by inner shells

Question 15

What causes induced dipole-diploma infractions ?

Answer 15

Random movement of electrons which unbalances the distribution of charge within the electron shells. The instantaneous dipole is

Question 16

atomic orbital

Answer 16

a region around a nucleus that can hold up to two electrons with opposite spins

Question 17

Melting and boiling point of a ionic compund?

Answer 17

• high melting and boiling point as it requires large amount of energy to overcome the strong electrostatic forces of attraction between the ions

Question 18

Simple covalent structure

Answer 18

• strong covalent bonds within the atoms

- weak intermolecular forces such as van der waals between the molecules

Question 19

Properties of simple molecular structures

Answer 19

• low melting and boiling points as they have weak intermolecular forces
• do not conduct electricity as there are no charged particles
• soluble as the weak forces can be broken down

Question 20

Properties of a giant covalent structure

Answer 20

• high melting and boiling point
• do not conduct electricity as they has no charged ions
• insoluable covalent bonds are too strong to be broken

Question 21

effect of lone pairs

Answer 21

lone pairs repel more than other bonding pairs soo decrease other bond angles by 2.5 degrees

Question 22

hydrogen bonding

Answer 22

intermolecular bonding
between molecules containing N, O or F and the
H atom of –NH, –OH or HF