Questiks Tesr

Question 1

Defined the term first ionisation energy

Answer 1

The energy required to remove an electron from each atom in one mole of atoms in gaseous state

Question 2

What is periodicity

Answer 2

Repeating pattern of properties across the periodic table

Question 3

Write an equation for bleach

Answer 3

2NaOH + Cl2 —>NaClO + NaCl + H2O

Question 4

A sample of Brine is a concentrated Aquarius solution of NaCl describe a simple chemical test that you could carry out to show the brine contains Aquarius chloride irons how would you confirm that no other halide ions are present include ionic equations in your answer

Answer 4

Add silver nitrate to cl- if a white precipitate is formed Cl- is present
Ag+ + cl- —> AgCl
Add dilute NH3 and if the precipitate completely dissolves

Question 5

Group 2 elements also react with dilute hydrochloric acid describe and explain the trend in reactivity of the group 2 elements with dilute hydrochloric acid as the group is descended

Answer 5

Reactivity increases down the group as there is more shielding on the outer most electron has less nuclear attraction so it’s easier to remove the outermost electron so reactivity increases

Question 6

Solid SIO2 melts at 2230°C solid SICL4 melt at -70° neither of the liquid form conducts electricity suggest the type of lattice structure in solid SIO2 and in solid SICL4 and explain the difference in Melting points in terms of bonding and structure

Answer 6

SIO2 is a giant covalent SICL4 is a simple molecule SICL4 has Vander walls forces and covalent bonds are broken in SIO2 forces are stronger in SIO2 so more energy is required to break forces mean in the boiling point is higher

Question 7

Define relative atomic mass

Answer 7

The weighted mean mass of an atom relative to 1/12 of the mass of a carbon 12 atom

Question 8

What is metallic bonding

Answer 8

metallic bond as (electrostatic) attraction between the electrons and the positive ions

Question 9

Write the equation for the reaction of sodium with oxygen to form sodium oxide

Answer 9

4 Na + O2 —> 2 Na2O

Question 10

What is ionic bonding

Answer 10

Electrostatic attraction between oppositely charged ions

Question 11

Explain why the first ionisation energy sure a general increase from li to Ne

Answer 11

outer electrons closer to nucleus
nuclear charge increases
shielding remains the same

Question 12

Explain the difference in first ionisation energies of LI and Na

Answer 12

atomic radii increase
there is more shielding
the nuclear attraction decreases

Question 13

Write an equation to represent the second ionisation energy of oxygen including state symbols

Answer 13

O+(g) —> O2+(g + e–

Question 14

Suggest why the second ionisation energy of oxygen has a greater value than the first ionisation energy

Answer 14

the electron repulsion/shielding is smaller

Question 15

What is meant by the term atomic number

Answer 15

Number of protons in the nucleus

Question 16

State the formula of the two ions are released when sulphuric acid is an Aquarius solution

Answer 16

H plus SO42 minus

Question 17

A student as a sample of solid potassium carbonate to an excess of dilute sulphuric acid describe what the student would see and write the equation for the reaction which place takes place

Answer 17

 Effervescence
potassium carbonate dissolve

H2SO4 + K2CO3 —> K2SO4 + CO2 + H2O

Question 18

What is meant by an orbital

Answer 18

A region of space that can hold up to 2 electrons

Question 19

What colour does Cl2 turn to when you add I- ions

Answer 19

Purple

Question 20

What colour does Br2 turn to when you add Cl- ions

Answer 20

Orange

Question 21

Eqquation for addition of CL2 to Br- ions

Answer 21

Cl2 +2Br– —> 2Cl– + Br2

Question 22

These three experiments alone are unable to confirm the order of reactivity for Chlorine bromine and iodine suggest one further displacement reaction which could be carried out to confirm the order of reactivity Of chlorine bromine and iodine

Answer 22

Addition of Br2(aq) to I–(aq) ions

Question 23

What is relative isotopic mass

Answer 23

The mass of an isotope compared to 1/12 of a carbon 12 atom

Question 24

Explain why xenon has a lower first ionisation energy than neon

Answer 24

Xenon has a bigger atomic radius
Xenon has more shielding
So the outermost electron has less nuclear attraction

Question 25

Predict the bond angle in a F2O molecule explain your answer

Answer 25

104

There are two bonded pairs and to lone pairs lone pairs repel more than bonded pairs

Question 26

A student has a solution that contains bromide ions the student carries out the following experiment step one Wilson chlorine gas through the sample of the solution the mixture changes colour write an ionic equation for the reaction that takes place in the step

Answer 26

Cl2 + 2Br- → Br2 + 2Cl–

Question 27

A student has a solution that contains bromide ions the student code of the following experiment step to the student then add an organic solvent cyclohexane to the mixture she shakes the content and allows the latest to separate what colour does the cyclohexane turning step to

Answer 27

Yellow

Question 28

Why does ICl have a higher boiling point than Cl2

Answer 28

ICl has more electrons. ORA
ALLOW I has more electrons ALLOW more van der Waals’ forces
Stronger van der Waals’ forces in ICl (than in Cl2) ORA OR
More energy is needed to overcome van der Waals’ forces in ICl ORA

Question 29

11
(b)
The hydrazine molecule, H,N-NH2, is covalent.
Predict the H-N-H bond angle in a hydrazine molecule.
Explain your answer.

Answer 29

Predicted bond angle 107o

There are 3 bonded pairs and 1 lone pair

Electron pairs repel
Lone pairs repel more than bonded pairs

Question 30

What is electronegativity

Answer 30

The ability of an atom to attract electrons in a covalent bond