PAST PAPER CONTENT Flashcards
Fc6Would Ions with a greater charge be deflected more in a Mass Spectrometer
Yes !
Ions with a greater charge would be more deflected in a Mass Spectrometer
Because there is a greater force
Dative Covalent Bonding Definition?
A Two center, Two Electron covalent bond in which these two electrons derive from the same atom
How to Draw Carbon Monoxide ?
Diagram
Polar vs Non-Polar
Hydrocarbons are non-polar
Symmetry = Polar
Polar>0.5 EN
Examples of Polar Molecules?
H- N,O,F
H20, NH3, HF
What line is it on the EM if an electron emits energy to N=1, N=2, N=3 ?
UV-Radiation n=1
Visible Light Transition n=2
Infrared Radiation Transition n=3
Is Combustion exothermic or endothermic
exothermic
Is Decomposition endo or exo?
endo
Is neutralisation exo or endo?
exo
What three processes go on in Mass Spectrometry?
Ionization, Acceleration and Deflection
Outline the three processes in Mass Spectrometry.
ionization: sample bombarded with high-energy or high-speed
electrons/OWTTE;
acceleration: electric field/oppositely charged plates;
deflection:
(electro)magnet/magnetic field;
Electrolytic Cell Diagram?
See Answer
Define the term activation energy
the minimum quantity of energy which the reacting species must possess in order to undergo a specified reaction.
Distinguish between a strong and a weak acid
Weak Acid- Partially Ionizes in Solution
Enthalpy Change
The Enthalpy change is independent of the route taken
The definition of the standard enthalpy of formation, ΔHf, is:
The enthalpy change when 1 mole of a compound is formed from its elements; [1]
In their standard states; [1]
The equation for the formation of the following compounds are?
Methanol
Carbon Dioxide
Ethane
C (s) + ½O2 (g) + 2H2 (g) → CH3OH (l)
C (s) + O2 (g) → CO2 (g)
2C (s) + 3H2 (g) → C2H6 (g)
Which properties increase as you go down group 1?
Atomic Radius
Electronegativity
First Ionization Energy
Which properties decrease as you go down group 1?
Melting Point
What does the strength of Metallic Bonding depend on?
Ionic radius and charge
Smaller Ionic Radius –> Stronger Bonding
Greater Charge –> Stronger Bonding
Are enthalpy changes accurate and how do they compare to enthalpy change of formation?
Bond Enthalpies are not specific to compounds - averages are taken from the data booklet
Enthalpy Changes of Formation are specific
Equation for Equilibrium Constant?
[C}X{D}/[A}X[B]
Does a weak acid have poor conductivity?
Yes
Are neutralisation reactions redox?
Neutralisation reactions are not redox
Describe the reaction between halogen and ethane?
Free radical substitution and homolytic
In the equation Pv = nRT, what is the relationship between n and T?
Inverse Relationship
S,P,D,F on the periodic table?
SEE
What is true about Strong Acids
They are good proton donors and they have weak conjugate bases
What Compund is the exception to the rule that O2 has a -2 Oxidation number?
H2O2 - Hydrogen Peroxide where it has an oxidation number of -1
Suggest two reasons why atoms are no longer regarded as the indivisible units of matter.
subatomic particles «discovered»
OR
particles smaller/with masses less than atoms «discovered»
OR
«existence of» isotopes «same number of protons, different number of neutrons»✔
charged particles obtained from «neutral» atoms
Lewis Structure for Ammonia
See?
Suggest why the Bond enthalpy might not be right?
«N-H» bond enthalpy is an average «and may not be the precise value in NH3»
Suggest an experiment to show that one metal is more reactive than the other
MG and ZN
Alternative 3
construct a cell with Mg and Zn electrodes ✔
bulb lights up
OR
shows (+) voltage
OR
size/mass of Mg(s) decreases «over time»
OR
size/mass of Zn increases «over time»
Brønsted–Lowry acid.
fully ionizes/dissociates ✔
proton/H+ «donor »✔
Explain the trend of ionisation energy across a period
Left to right
Ionisation energy increases
Ionisation Energy
Minimum energy required to remove the most loosely bound electron of an isolated gaseous atom, positive ion, or molecule
do Metallic Bonds have low ionisation energies?
Yes - low Ionisation energies
They lose electrons so removing them is a tough one for them!
State the trend between ionisation energy and group number?
Going down a group the ionisation energy decreases
Do Metallic Bonds have a large atomic radii?
Yes - Metallic Bonds have laerg atomic radii
Do Metallic Bonds have high EM values?
No - on the lower end
Can you arrange the electron configuration in a periodic table?
SEE
State the trend between Atomic Radius and a group and explain the reason why?
As you go down the group the Atomic Radius increases
This is because there are more Shells
Although there may be greater nuclear charge –> effect counteracted due to a greater number of protons
State the trend between Atomic Radius and the period number? and explain why?
Atomic radius decreases across a period
BECAUSE
Nuclear charge increases with no significant change in shielding
Shielding remains approximately constant –. Atoms in the same period have the same number of inner shells
Compare the size of ionic and atomic radii?
Ionic radii of positive ions are smaller than their atomic radii
Ionic radii of negative ions are greater than their atomic radii
Why is Na larger than Na+?
Na has one extra shell
They both have the same nuclear charge
Greater amount of electron repulsion –> Greater amount of e-
Larger e- cloud in Na because there are more electrons repelling for the same nuclear charge
How does charge change with ionic radius?
Positive ions –> Decrease in radius as the charge increases
Negative –> Increase in radius as the charge increases
How Volatile are Ionic Compounds?
Low volatility
Strong electrostatic forces of attraction
How soluble are Ionic Compounds in Water?
Often soluble in water.
Water is a polar solvent and energy is released when the ions are hydrated by being surrounded by water molecules.
Energy pays back energy required to break apart the ionic lattice
How soluble are Ionic Compounds in non-Polar solvents?
Great deal of energy required to break apart the ionic lattice
Energy is not paid back by the energy released when the non-polar solvent forms interactions with ions
Metal Oxide + Water
Metal Hydroxide
Metal + Base
Salt + Hydrogen
Acid + Metal + Carbonate
Salt + Water + Hydrogen
Are Metal Oxides basic or acidic?
Are Non Metal Oxides basic or acidic?
Basic
Acidic - non Metal
Outline the electron configuration of a Hydrogen Emission spectrum?
E- occupy discrete energy levels
Energy Levels converge
BOND ANGLE DIAGRAM
SEE
4 E- Pair and 1 lone pair
Trigonal Pyramidal
rate of reaction def
the increase in the concentration of product per unit time.
metalloid?
Elements with a mixture of metallic and non-metallic physical properties
Closed system
A system in which neither matter nor energy can be lost or gained. An equilibrium can never occur in a system that is not closed
Homogeneous reaction
A reaction in which all the species involved are in the same phase.
Le Chatelier’s principle
If an equilibrium is subjected to a stress, the equilibrium will shift to minimize the effect of the stress.
Amphoteric and Amphriprotic
Amphiprotic species specifically refer to species that can donate or accept a proton (H+ ion). So, a molecule or ion that is amphiprotic must have at least one hydrogen atom that can be ionized, allowing it to act as an acid or a base.
On the other hand, amphoteric species refers to substances that can react with both acids and bases, not necessarily by donating or accepting a proton. This means that an amphoteric species can act as an acid in the presence of a base, and as a base in the presence of an acid.
Orbital:
A region of space around the nucleus of an atom that is occupied by a maximum of two electrons at any given time.
Orbital:
A region of space around the nucleus of an atom that is occupied by a maximum of two electrons at any given time.
Electronegativity
Relative measure of the ability an atom has to attract a shared pair of electrons.
Allotropes
Occur when an element can exist in different crystalline forms, such as in carbon, which can exist as graphite, fullerene and diamond.
Allotropes
Occur when an element can exist in different crystalline forms, such as in carbon, which can exist as graphite, fullerene and diamond.
Electron affinity
Enthalpy change when an electron is added to an isolated atom in the gaseous state.
Electron affinity
Enthalpy change when an electron is added to an isolated atom in the gaseous state.
Buffer
A solution that resists changes in pH when small amounts of acid or alkali are added to it.
Enthalpy of Combustion
The energy released when one mole of a compound is burned in excess oxygen.
Standard enthalpy of formation
The energy change when one mole of a compound is formed under standard conditions from its constituent elements in their standard states.
Standard enthalpy of solution
: The energy change when one mole of a substance is dissolved in an infinite amount of water under standard conditions.
Aufbau principle
The principle that states that lowest energy levels are filled first.