topic 2- bonding, structure and properties of matter

Question 1

describe how an ionic bond forms

Answer 1

when a metal and a nonmetal bond, the metal loses electrons to form a positively charged ion and the nonmetal will gain electrons to become a negatively charged ion. then these oppositely charged ions form a strong attraction called an ionic bond

Question 2

which group of the periodic table contains elements which form ions with a +1 charge

Answer 2

group 1

Question 3

which group of the periodic table contains elements which form ions with a -1 charge

Answer 3

group 7

Question 4

describe the structure of a crystal of sodium chloride

Answer 4

the sodium atom loses it’s outer electron, becoming an Na+ ion, and the chlorine atom will pick up the electron, becoming a Cl- ion

Question 5

list the main properties of ionic compounds

Answer 5

a giant lattice structure, high melting and boiling points, cannot conduct electricity as solids, can conduct electricity when melted or dissolved in water

Question 6

describe how covalent bonds form

Answer 6

when nonmetals react, they share electrons as they all need to gain electrons to have a full outer shell. each singly covalent bond provides one extra shared electron for each atom

Question 7

explain why simple molecular compounds typically have low melting and boiling points

Answer 7

the intermolecular bonds are incredibly weak, so seperating the bonds is really easy, so a very low melting or boiling point is required

Question 8

describe the structure of a polymer

Answer 8

lots of small units that are linked to form a long molecule with repeating sections. all of atoms in polymers are held together by strong covalent bonds

Question 9

what type of bond occurs between carbon atoms in diamond

Answer 9

covalent

Question 10

describe the structure of graphene

Answer 10

a sheet of carbon ions joined together in hexagonal shapes that is only one atom thick, making it a two dimensional substance and it contains delocalised electrons so it can carry electricity and heat well

Question 11

what is metallic bonding

Answer 11

when electrons in the outer shell of metals are delocalised, there are strong forced of attraction between the positively charged metal ions and the shared negative electrons

Question 12

explain why metals have good conduction of heat and electricity

Answer 12

they have delocalised electrons in their formations so the electrons can easily carry energy throughout the material

Question 13

explain why metals are solid at room temperature

Answer 13

metallic bonding is incredibly strong so it requires a lot of energy to break the bonds, so the bonds cannot be broken at room temperature (except for mercury)

Question 14

name the three states of matter

Answer 14

solid, liquid, gas

Question 15

what is the name of the temperature at which a liquid becomes a gas

Answer 15

boiling point

Question 16

how does the strength of the forced between particles influence the temperature at which a substance changes state

Answer 16

the stronger the bonds are, the more energy it will need to break them, so you need a higher temperature in order to be able to break the bonds

Question 17

what is the state symbol of a solid substance

Answer 17

(s)

Question 18

what is nanoscience

Answer 18

the use of nanoparticles

Question 19

give three uses of nanoparticles

Answer 19

make new catalysts, in cosmetics to make moisturiser less oily, used in tiny electric circiuts for computer chips