atomic structure and bonding

Question 1

define the term atom

Answer 1

smallest particle of any matter that enters a chemical reaction

Question 2

define the term element

Answer 2

a substance made up of only one type if atom

Question 3

define the relative atomic mass

Answer 3

total number of neutrons and protons (nucleons) in an atoms nucleus

Question 4

define the term atomic number

Answer 4

number of protons (and electrons) of an atom

Question 5

define the term isotope

Answer 5

atoms of the same element with the same proton number but different nucleon number

Question 6

why do isotopes share the same chemical properties

Answer 6

because they have the same number of electrons and chemical properties are determined by the number of electrons

Question 7

why do isotopes of the same element have different physical properties

Answer 7

because they have different nucleon numbers

Question 8

give 2 uses of radioactive isotops

Answer 8

U235 in nuclear power stations to release energy
cure cancer

Question 9

define the term compound

Answer 9

substance made up of two or more atoms of the same or different element chemically bonded

Question 10

define the term mixture

Answer 10

a substance made of two or more substances not chemically bonded only physically mixed

Question 11

define the term ionic bonding

Answer 11

total transfer of electrons

Question 12

define the term covalent bond

Answer 12

sharing of electrons

Question 13

define the term metallic bond

Answer 13

attraction force between positive metal ions and electrons in metals

Question 14

what force is found in ionic compounds

Answer 14

electrostatic

Question 15

why do ionic compounds exist as solids (hard crystals)

Answer 15

due to strong electrostatic forces of attraction

Question 16

why do ionic compounds have high mp and bp

Answer 16

due to strong electrostatic forces of attraction

Question 17

why are ionic compounds soluble in water

Answer 17

water is able to form strong electrostatic forces with the ions, separating them

Question 18

in which state do ionic compounds conduct electricity? explain your answer.

Answer 18

when molten or aqueous
due to the presence of free, mobile ions

Question 19

all ionic compounds exist as (giant/simple) ionic compounds

Answer 19

giant

Question 20

define the term lattice

Answer 20

3D regular arrangement of positive and negative ions

Question 21

define the term covalent bonding

Answer 21

the sharing of electrons between two non metals resulting in the formation of a molecule

Question 22

give 4 physical properties of simple covalent molecules

Answer 22

exist as liquids or gases

low mp and bp (due to weak intermolecular forces)

insoluble in water but soluble in organic solvents

dont conduct electricity (no free moving ions or electrons)

Question 23

state the different between intermolecular and intramolecular forces

Answer 23

intermolecular is the weak force between molecules

intramolecular is the strong covalent bond between atoms

Question 24

give another name for giant covalent molecules

Answer 24

macromolecules

Question 25

define the term allotrope

Answer 25

different form of the same element

Question 26

what shape does graphite take

Answer 26

hexagonal layers

Question 27

give three properties of graphite

Answer 27

high mp and bp
conduct electricity due to the presence of mobile electrons
soft and slippery

Question 28

name the uses of graphite

Answer 28

pencils/lubricants, as its soft and slipper

electrodes, as it conducts electricity

Question 29

what shape does a diamond take

Answer 29

tetrahedral

Question 30

give three properties of diamond

Answer 30

hard and strong
high mp and bp
cant conduct electricity (no mobile electrons)

Question 31

what property of diamonds make it suitable for the making of jelwery

Answer 31

shiny appearance

Question 32

why are diamonds used for cutting and drilling

Answer 32

bc theyre hard and strong