Y13 Chem mock

Question 1

Why are do isotopes have similar chemical properties

Answer 1

Same electron configuration which affects the chemical properties of the atoms

Question 2

Why do isotopes have different physical properties

Answer 2

due to the differing masses of the atoms they can have different densities

Question 3

What did jj thompson add to the understanding of chemistry

Answer 3

The atom contains negatively charged particles called electrons, devised the plum pudding model(positive charge with small negative charges dotted)

Question 4

What did rutherford add to the understanding of chemistry

Answer 4

He fired alpha particles at a thin sheet of gold most of the particles went straight through which suggests the atom isn’t entirely positive some of them were reflected. Suggested nuclear model positive nucleus with clouds of electrons that float around it

Question 5

What modifications did rutherford add

Answer 5

Realised that nucleus had positive charge that varied between atoms, determined existence of protons

Question 6

What did james chadwick discover

Answer 6

Existence of neutrons

Question 7

What is relative atomic mass

Answer 7

Ar is the weighted mean mass of an element compared to 1/12 the mass of an atom of C-12

Question 8

What is the relative isotopic mass

Answer 8

Mass of an atom of an isotope compared to 1/12 the mass of c12

Question 9

What is molar mass

Answer 9

The mass of one mole of something (“g mol-1)

Question 10

What is the gas volume equation

Answer 10

number of moles = volume in dm3/24

Question 11

what is room temp and pressure

Answer 11

298k, 100kPa

Question 12

Ideal gas equation and units

Answer 12

pV = nRT
p = Pa kPa to Pa *1000
V= dm3 cm to dm3 /1000 dm3 to m3 /1000
n= moles
R=8.314
T= K *c + 273

Question 13

concentration equation

Answer 13

moles= conc * volume (dm3)

Question 14

what is the empirical formula

Answer 14

smallest number ratio of atoms in a com pound

Question 15

Important ions

Answer 15

Nitrate- No3-
Carbonate- CO32-
SO42-
OH-
NH4+

Question 16

What are acids, main ones

Answer 16

proton donors
HCL
H2SO4
HNO3(nitric)
CH3COOH(ethanoic acid

Question 17

what are bases, common bases

Answer 17

proton acceptors
NaOH
KOH
NH3

Question 18

What is the reaction between ammonia and H20

Answer 18

NH3 + H20 -> NH4+ + OH-
reversible

Question 19

Strong bases/ acids

Answer 19

HCL fully dissociates in water, and nearly all the H+ ions are released

Question 20

weak bases/ acids

Answer 20

backward reaction favoured so small amoutns of acid dissociates in water and few H+ ions are released

Question 21

Acid + Base ->

Answer 21

Salt + Water

Question 22

Metal + Acid

Answer 22

Salt + Hydrogen

Question 23

Metal oxide + Acid

Answer 23

Salt + Water

Question 24

Metal hydroxide + Acid

Answer 24

Salt + Water

Question 25

What is the principal quantum number

Answer 25

energy levels in which electrons lie(shells)

Question 26

What are subshells

Answer 26

Further division of the shells

Question 27

What are orbitals

Answer 27

Areas of space in which electrons can be found(cloud) can only hold up to 2 electrons

Question 28

What main property of electron

Answer 28

quantum property of spin, they spin in opposite directions they also repel each other to an extent

Question 29

What is a giant ionic lattice

Answer 29

repeating regular structure of ironically bonded atoms

Question 30

Behaviours of ionic compounds

Answer 30

conductivity in molten/dissolved because ions can move and carry charge high melting and boiling points ionic compounds are held together by lattice which has strong electrostatic forces soluability can dissolve in water due to charges hydrogen bonds can form

Question 31

What is a dative bond

Answer 31

when an atom donates 2 electrons on its own in a covalent bond

Question 32

What are the special cases for covalent bonds

Answer 32

Boron trifluoride (6 electron in outer shell) Sulphur hexafluoride expands the octet and has 12 electrons in its outer shell

Question 33

What is average bond enthalpy

Answer 33

the energy required to break a covalent bond

Question 34

Linear shape

Answer 34

2 bonding pairs no lone pairs(180)

Question 35

trigonal planar

Answer 35

3 bonding pairs (120)

Question 36

tetrahedral

Answer 36

4 bonding pairs(109.5)

Question 37

trigonal pyramidal

Answer 37

3 bonding pairs 1 lone pair (107)

Question 38

non-linear

Answer 38

2 bonding pairs 2 lone pairs(104.5)

Question 39

trigonal pyramidal

Answer 39

5 bonding pairs 120 and 90

Question 40

octahedral

Answer 40

6 boning pairs(90)