KERBOODLE SUMMARY QUESTIONS: EL COPY Flashcards
Complete the table


State the number of protons, neutrons, and electrons present in

35 protons
44 neutrons
35 electrons
State the number of protons, neutrons, and electrons present in

35 protons
46 neutrons
35 electrons
State the number of protons, neutrons, and electrons present in

17 protons
18 neutrons
17 electrons
State the number of protons, neutrons, and electrons present in

17 protons
20 neutrons
17 electrons
Using the isotopes and their abundances, work out the relative atomic mass of bromine
Ar of Br = 80.0
Using the isotopes and their abundances, work out the relative atomic mass of bromine
Ar of Ca = 40.1
The relative atomic mass of the element iridium is 192.2. Iridium occurs naturally as a mixture of iridium-191 and iridium-193.
Calculate the percentage of each isotope in naturally occuring iridium if the value for the relative atomic mass is taken to be 192.2
take iridium-193 to be x%
iridium-191 = 100-x%
193x and 191(100-x)
(193x+19100-191x)/100 = 192.2
2x+19100=19220
2x=19220-19100
2x=120
x=60
iridium-193 = 60% iridium-191 = 40%
Write a nuclear equation for a 7Li nucleus that absorbs a colliding proton and then disintegrates into two identical fragments

Write a nuclear equation for the production of carbon-14 by collision of a neutron with an atom of nitrogen-14

The relative atomic mass of antimony is 121.8. Antimony exists as two isotopes - antimony-121 and antimony-123.
Calculate the relative abundances of the two isotopes
antimony-123 = 40% antimony-121 = 60%
Lithium carbonate is used to give the bright red colour to a firework. The visible region of the emission spectrum of lithium contains several coloured lines with a particularly intense line at the red end of the spectrum. The emission spectrum is shown below
Which line, green or red, has a greater frequency?

green
Flame tests can be used to identify some metal cations.
What is the flame colour for Li+?
bright red
Flame tests can be used to identify some metal cations.
What is the flame colour for Na+?
orange
Flame tests can be used to identify some metal cations.
What is the flame colour for K+?
lilac
Flame tests can be used to identify some metal cations.
What is the flame colour for Ca2+?
brick red
Flame tests can be used to identify some metal cations.
What is the flame colour for Ba2+?
apple green
Flame tests can be used to identify some metal cations.
What is the flame colour for Cu2+?
blue-green
Describe the similarites and differences between an emission spectrum of lithium and an absorption spectrum of lithium
Similarities: line spectrum; lines in the same place because have same frequencies
lines get closer together with increasing frequency
Differences: black lines on a bright coloured continuous spectrum background for absorption spectrum
Draw an energy level diagram with two arrows. One to represent an electron energy level change that might give rise to the red line and the other to represent an energy level change that might give rise to the green line.

both arrows pointing downwards
shorter arrow represents red line
longer arrow represents gree line
both arrows must start and finish on lines; does not matter which levels they go between

Calculate the frequency of electromagnetic radiation with a wavelength of 5.5 x 10-7m
5.5 x 1014 s-1
1s2 is an example of a notation for electronic configuration
What does the number 1 refer to?
The electrons are in the first electron shell
1s2 is an example of a notation for electronic configuration
What does the s refer to?
The electrons are in an s type orbital
1s2 is an example of a notation for electronic configuration
What does the superscript 2 refer to?
There are two electrons in this orbital
Write out the electronic configuration for boron (Z=5)
1s22s22p1
Write out the electronic configuration for phosphorus (Z=15)
1s22s22p63s23p3
The electronic configuration of the outermost shell of an atom of an element X is 3s23p4
What is the atomic number and name of the element
Z=16
element is sulfur
Electronic configurations are sometimes abbreviated by labelling the core of filled inner shells as the electronic configuration of the appropriate noble gas.
Name the element from the electronic configuration [Ne] 3s23p5
chlorine
Electronic configurations are sometimes abbreviated by labelling the core of filled inner shells as the electronic configuration of the appropriate noble gas.
Name the element from the electronic configuration [Ar] 4s1
potassium
Electronic configurations are sometimes abbreviated by labelling the core of filled inner shells as the electronic configuration of the appropriate noble gas.
Name the element from the electronic configuration [Ar] 3d24s2
titanium
Electronic configurations are sometimes abbreviated by labelling the core of filled inner shells as the electronic configuration of the appropriate noble gas.
Name the element from the electronic configuration [Kr] 4d105s25p2
tin
The electron shell configuration for sodium can be written as 2.8.1.
Use this notation to write down the electron configuration for lithium
2.1
The electron shell configuration for sodium can be written as 2.8.1.
Use this notation to write down the electron configuration for phosphorus
2.8.5
The electron shell configuration for sodium can be written as 2.8.1.
Use this notation to write down the electron configuration for calcium
2.8.8.2
The electron shell configurations of unknown elements A to E are given below. Which of these elements are in the same group?
A) 2.8.2
B) 2.6
C) 2.8.8.2
D) 2.7
E) 2.2
A, C and E
Complete the table below


Classify the element [Kr] 5s1 as a s-, p-, d-, or f-block element
s-block
Classify the element 1s22s22p63s23p4 as a s-, p-, d-, or f-block element
p-block
Classify the element [Ar] 3d104s24p6 as a s-, p-, d-, or f-block element
p-block
Classify the element [Xe] 6s2 as a s-, p-, d-, or f-block element
s-block
Classify chromium as a s-, p-, d-, or f-block element
d-block
Classify aluminium as a s-, p-, d-, or f-block element
p-block
Classify uranium as a s-, p-, d-, or f-block element
f-block
Classify strontium as a s-, p-, d-, or f-block element
s-block
Draw an electron dot-and-cross diagram for chlorine, Cl2

Draw an electron dot-and-cross diagram for hydrogen chloride, HCl

Draw an electron dot-and-cross diagram for methane, CH4

Draw an electron dot-and-cross diagram for hydrogen sulfide, H2S

Draw an electron dot-and-cross diagram for aluminium bromide, AlBr3

Draw an electron dot-and-cross diagram for silicon chloride, SiCl4

Draw an electron dot-and-cross for ethene

Draw an electron dot-and-cross for ethyne

Draw an electron dot-and-cross for methanol

Ammonia, NH3, and boron trifluoride, BF3, combine together to form the molecule NH3BF3
This molecule has a dative covalent bond between the nitrogen atom and the boron atom
Draw a dot-and-cross diagram for this molecule

Draw an electron dot-and-cross diagram to show the bonding pairs and lone pairs of electrons in SiH4. Give the bond angles you would expect.
109.5

Draw an electron dot-and-cross diagram to show the bonding pairs and lone pairs of electrons in H2S. Give the bond angles you would expect.
104.5

Draw an electron dot-and-cross diagram to show the bonding pairs and lone pairs of electrons in PH3. Give the bond angles you would expect.
107

Draw an electron dot-and-cross diagram to show the bonding pairs and lone pairs of electrons in CO2. Give the bond angles you would expect.
180

Draw an electron dot-and-cross diagram to show the bonding pairs and lone pairs of electrons in SF2. Give the bond angles you would expect.
104.5

Draw an electron dot-and-cross diagram to show the bonding pairs and lone pairs of electrons in BCl3. Give the bond angles you would expect.
120

Draw an electron dot-and-cross diagram to show the bonding pairs and lone pairs of electrons in C2H2. Give the bond angles you would expect.
180

Draw a diagram to show the bonds and lone pairs of electrons in CH3CH3. Give the bond angles you would expect.
109.5

Draw a diagram to show the bonds and lone pairs of electrons in CH3OH. Give the bond angles you would expect.

Draw a diagram to show the bonds and lone pairs of electrons in CH3NH2. Give the bond angles you would expect.

Draw a diagram to show the bonds and lone pairs of electrons in CH2=CH2. Give the bond angles you would expect.
120

Draw a diagram to show the bonds and lone pairs of electrons in CH3C≡N. Give the bond angles you would expect.

Draw a diagram to show the bonds and lone pairs of electrons in NH2OH. Give the bond angles you would expect.
no answer in textbook = ask miss
Draw a diagram to show the bonds and lone pairs of electrons in COCl2. Give the bond angles you would expect.
textbook doesnt give an answer = ask miss
What shape is NF3?
pyramidal
What shape is BF3?
trigonal planar
What shape is SF6?
octahedral
One atom of element X is approximately 12 times heavier than one carbon atom.
What is the approximate relative atomic mass of this element? Hence identify X.
relative atomic mass = 144
neodymium, Nd
Balance the equation:
Mg + O2 –> MgO
2Mg + O2 –> 2MgO
Balance the equation:
H2 + O2 –> H2O
2H2 + O2 –> 2H2O
Balance the equation:
CaCO3 + HCl –> CaCl2 + CO2 + H2O
CaCO3 + 2HCl –> CaCl2 + CO2 + H2O
Balance the equation:
HCl + Ca(OH)2 –> CaCl2 + H2O
2HCl + Ca(OH)2 –> CaCl2 + 2H2O
Balance the equation:
CH3OH + O2 –> CO2 + H2O
2CH3OH + 3O2 –> 2CO2 + 4H2O
Write a balanced equation including state symbols for zinc reaction with sulfuric acid to form zinc sulfate and hydrogen.
Zn(s) + H2SO4(aq) –> ZnSO4(aq) + H2(g)
Write a balanced equation including state symbols for magnesium carbonate, MgCO3, decomposing on heating to form magnesium oxide and carbon dioxide
MgCO3(s) –> MgO(s) + CO2(g)
Write a balanced equation including state symbols for barium oxide reacting with hydrochloric acid to form barium chloride and water.
BaO(s) + 2HCl(aq) –> BaCl2(aq) + H2O(l)
The empirical formula of a compound can be calculated when you know the masses of the elements in a sample of it.
The steps to calculate the empirical formula of a compound if a 16.7g sample of it contains 12.7g of iodine and 4.0g of oxygen is shown below (Units have been omitted)
Why do we need to know the mass of the sample as well as the masses of the elements in it?

The mass of the sample is needed to be sure that iodine and oxygen are the only elements in the compound
The empirical formula of a compound can be calculated when you know the masses of the elements in a sample of it.
The steps to calculate the empirical formula of a compound if a 16.7g sample of it contains 12.7g of iodine and 4.0g of oxygen is shown below (Units have been omitted)
In step 2, what do the numbers 0.1 and 0.25 represent?

The relative number of moles of iodine and oxygen
The empirical formula of a compound can be calculated when you know the masses of the elements in a sample of it.
The steps to calculate the empirical formula of a compound if a 16.7g sample of it contains 12.7g of iodine and 4.0g of oxygen is shown below (Units have been omitted)
Why, in step 3, do we divide both 0.1 and 0.25 by 0.1?

To change the relative number of moles into the ratio of moles of oxygen relative to 1 mole of iodine
The empirical formula of a compound can be calculated when you know the masses of the elements in a sample of it.
The steps to calculate the empirical formula of a compound if a 16.7g sample of it contains 12.7g of iodine and 4.0g of oxygen is shown below (Units have been omitted)
Why have we doubled the numbers in moving from step 3 to 4?

In order to produce a ratio involving whole numbers
The empirical formula of a compound can be calculated when you know the masses of the elements in a sample of it.
The steps to calculate the empirical formula of a compound if a 16.7g sample of it contains 12.7g of iodine and 4.0g of oxygen is shown below (Units have been omitted)
Write down three possibilities for the molecular formula of this compound based on its empirical formula

I2O5, I4O10, I6O15 etc.
The empirical formula of a compound can be calculated when you know the masses of the elements in a sample of it.
The steps to calculate the empirical formula of a compound if a 16.7g sample of it contains 12.7g of iodine and 4.0g of oxygen is shown below (Units have been omitted)
What additional information do you need to work out the actual molecular formula of the compound?

The molar mass is needed
How many moles of atoms are in 32.1g of sulfur?
1 mole
How many moles of atoms are in 31.8g of copper?
0.5 moles
Why would the moles of atoms in a sample of 32.1g of sulfur be different to the moles in a sample of 32.1g of copper?
Atoms of copper are approximately twice as heavy as atoms of sulphur
Thus around the same mass would contain only half as many moles of copper as it does of sulfur
How many moles are there in 88g of carbon dioxide?
2 moles
How many moles are there in 2.92g of sulfur hexafluoride, SF6?
0.02 moles
How many moles are there in 0.37kg of calcium hydroxide, Ca(OH)2?
5 moles
How many moles are there in 18 tonnes of water (1 tonne = 1 x 106g)?
1.0 x 106 moles
Draw an ionic dot-and-cross diagram for lithium hydride, LiH

Draw an ionic dot-and-cross diagram for potassium fluoride, KF

Draw an ionic dot-and-cross diagram for magnesium oxide, MgO

Draw an ionic dot-and-cross diagram for calcium sulfide, CaS

Which type of structure would you expect a white solid which starts to soften at 200oC and can be drawn into fibres to have?
macromolecular (covalent molecular)
Which type of structure would you expect a white solid which melts at -190oC to have?
simple molecular (covalent molecular)
Which type of structure would you expect a white solid which melts at 770oC and conducts electricity when molten, but not in the solid state
ionic (giant lattice)
Draw an ionic electron dot-and-cross for calcium chloride, CaCl2

Draw an ionic electron dot-and-cross for sodium sulfide, Na2S

An ammonia molecule, NH3, forms a dative bond with hydrogen ion, H+, to produce an ammonium ion, NH4+. The other three hydrogen atoms are held to the nitrogen atom by conventional covalent bonds.
What is the essential difference between a dative bond and a covalent bond?
In a normal covalent bond, each atom supplies a single electron to make up the pair of electrons involved in the bond. In a dative covalent bond one atom supplies both electrons.
An ammonia molecule, NH3, forms a dative bond with hydrogen ion, H+, to produce an ammonium ion, NH4+. The other three hydrogen atoms are held to the nitrogen atom by conventional covalent bonds.
Draw a dot-and-cross diagram for the ammonia molecule and the ammonium ion.

Which type of structure would you expect a hard grey solid which conducts electricity and melts at 3410oC to have?
ionic (giant lattice)
Which type of structure would you expect a liquid which conducts electricity and solidifies at -39oC to have?
metallic (giant lattice)
Draw an ionic dot-and-cross for sodium nitride, Na3N

Draw an ionic dot-and-cross for aluminium fluoride, AlF3

State two factors that affect the charge density of an ion
charge on the ion
radius of the ion
Write a word equation and a balanced chemical equation for the action of heated magnesium on steam
magnesium + steam –> magnesium hydroxide + hydrogen
Mg(s) + 2H2O(g) –> Mg(OH)2(s) + H2(g)
Write a word equation and a balanced chemical equation for the neutralisation of hydrochloric acid with calcium oxide
calcium oxide + hydrochloric acid –> calcium chloride + water
CaO(s) + 2HCl(aq) –> CaCl2(aq) + H2O(l)
Write a word equation and a balanced chemical equation for the thermal decomposition of beryllium carbonate
beryllium carbonate –> beryllium oxide + carbon dioxide
BeCO3(s) –> BeO(s) + CO2(g)
Write a word equation and a balanced chemical equation for the action of sulfuric acid on barium hydroxide
barium hydroxide + sulfuric acid –> barium sulfate + water
Ba(OH)2(aq or s) + H2SO4(aq) –> BaSO4(s) + 2H2O(l)
Write an equation for the first ionisation enthalpy of calcium
Ca(g) –> Ca+(g) + e-
Write an equation for the second ionisation enthalpy of calcium
Ca+(g) –> Ca2+(g) + e-
Write an equation for the third ionisation enthalpy of calcium
Ca2+(g) –> Ca3+(g) + e-
The first, second, and third ionisation enthalpies of calcium are +596kJ mol-1, +1160kJ mol-1, and +4930kJ mol-1 respectively
Explain why the second ionisation enthalpy of calcium is larger than its first ionisation enthalpy
Once an electron has been removed the remaining electrons are held more tightly. Hence it is more difficult to remove a second electron
The first, second, and third ionisation enthalpies of calcium are +596kJ mol-1, +1160kJ mol-1, and +4930kJ mol-1 respectively
Explain why there is a very sharp rise between the second and third ionisation enthalpies of calcium
Second ionisation enthalpy involves removal of an electron from shell 4 but third involves removal of an electron from shell 3 which is closer to the nucleus
Complete the table that shows the concentrations of ions in water from a sample of Dead Sea water


Calculate the mass of solute needed to make up 1 dm3 of a 2 mol dm-3 solution of NaCl
117g
Calculate the mass of solute needed to make up 250 cm3 of a 0.1 mol dm-3 solution of KMnO4
3.95g
Calculate the mass of solute needed to make up 50 cm3 of a 0.5 mol dm-3 solution of KOH
1.4g
Calculate the mass of solute needed to make up 15 dm3 of a 2 mol dm-3 solution of Pb(NO3)2
9930g
Calculate the mass of solute needed to make up 10 cm3 of a 0.01 mol dm-3 solution of LiOH
0.0024g
In a titration, 25.00 cm3 of a sodium hydroxide solution were pipetted into a conical flask. A 0.10 mol dm-3 solution of sulfuric acid was run from a burette into the flask. An indicator in the flask changed colour at an average of 22.00 cm3 of the acid added
H2SO4(aq) + 2NaOH(aq) –> Na2SO4(aq) + 2H2O(l)
What is the concentration of the sodium hydroxide solution in mol dm-3?
4.4 x 10-3 moles of NaOH(aq) in 25cm3 gives concentration 0.176 mol dm-3
In a titration, 25.00 cm3 of a sodium hydroxide solution were pipetted into a conical flask. A 0.10 mol dm-3 solution of sulfuric acid was run from a burette into the flask. An indicator in the flask changed colour at an average of 22.00 cm3 of the acid added
H2SO4(aq) + 2NaOH(aq) –> Na2SO4(aq) + 2H2O(l)
The student washes the conical flask with water between titrations and does not dry it. Explain the effect, if any, on the titre of the next titration.
No effect on next titre because pippette delivers same amount of NaOH(aq) as before
A standard solution of sodium hydroxide cannot be made by direct weighing of the solid
Explain the meaning of the term standard solution.
A solution of accurately known concentration
A standard solution of sodium hydroxide cannot be made by direct weighing of the solid
Suggest why sodium hydroxide cannot be made by direct weighing of the solid
Solid NaOH has the property of absorbing water (and carbon dioxide) from the air so it is not possible to accurately weigh NaOH