Bonding and Structure Flashcards
What is Deposition?
Gas –> Solid
Why, on a temperature time graph, does the temperature main constant at certain points?
All; the heat energy being supplied is used to partially overcome the forces of attraction between particles so that they can move around each other
What is an Element?
A pure substance that contains only one type of atom
What is a homogeneous mixture
Mixture has the same (uniform) composition throughout the mixture and consists of only one phase
What is a heterogeneous mixture?
Does not have uniform composition and consists of separate phases
These can be separated by mechanical means
Examples of a heteronegous mixture?
Sand in a beaker of water
Mixtures of different solids
Examples of homogeneous mixtures?
Solution
Clean Air
Table showing the relationship between the number of moles of molecules and the number of moles of particular atoms.
SEE
Do Isotopes have the same chemical and physical properties?
Chemical Properties - Same
Physical Properties - Different
What is the RAM?
Average of the masses of the isotopes in a naturally occurring sample of the element relative to the mass of 1/12 of an atom
What is the readout from a mass spectrometer?
Mass Spectrum
Explain why some Elements have more isotopes than other?
Some atoms are more stable than others
Outline two characteristics between N14 and N15?
Different Abundances and Differing M/Z ratios
What is a Mass Spectrometer used for?
To find out the RAM of Elements
The positive ions are deflected in a magnetic field depending on their mass to charge ratio (m/z or m/e). Ions with a higher mass to charge ratio are deflected less in the magnetic field than ions with a lower mass to charge ratio. Finally, the positive ions reach the detector, where they produce a mass spectrum.
What does a Mass Spectrometer do the element?
Turns it into a 1+ ion
What is Ionization Energy?
How do Isotopes affect Ionization Energy?
Fundamental property that affects the abillity to react
Trick question –> They don’t
What is the lowest energy also called?
K
Order of Sub-energy levels and orbitals Electronic Configuration?
Diagram:
Continuous Spectrum?
Line Spectrum?
Continuous Spectrum shows all wavelengths in a spectrum
A-Line Spectrum only shows certain wavelengths in a spectrum
Draw A Labelled diagram that shows electron transitions in the UV and V regions in the electromagnetic spectrum?
SEE
If an electrons energy is increased what happens to the energy level?
they jump to a higher energy level
Emission an Electron?
Ths is where E- are excited and go down an energy level
Which shells represent which EM wave?
ANSWERl:
Frequency and wavelength equation
c = vλ
The shape of a 1S atomic orbital?
Circle
The shape of a 2P Atomic Orbital?
Dumbell Shape
2P Atomic Orbitals?
Z - Vertical
X - Horizontal along the X axis
Y - Horizontal
Atomic orbital
An atomic orbital represents a region of space where there is a high probability of finding an electron
Do all Three 2P orbitals have the same energy?
Yeah
Is the 2S Orbitat bigger than the 1S Orbital?
Yes and its the same shape (spherical)
How Volatile Are Ionic Substances?
Low Volatility (refers to how readily a substance evaporates)
THIS IS BECAUSE THE ELECTROSTATIC FORCES OF ATTRACTION BETWEEN THE IONS ARE STRONG
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
This energy pays back the energy required to break apart the ionic lattice
How Soluble are Ionic Compounds in Non-Polar Solvents?
Not usually Soluble (hexane)
A great Deal of Energy is required to break apart the ionic lattice
This is not paid back by the energy released when the non-polar solvent forms interactions with the ions
Electronegativity
measure of the attraction of an atom in a molecule
for the electron pair
in the covalent bond of which it is a part
What is a Coordinate Covalent Bond?
A Coordinate Covalent bond is a type of covalent bond in which both electrons come from the same atom.
Would a triple bond be longer or shorter than a Double Bond?
Shorter but stronger
If Atoms have similar electronegativities what will they form?
Covalent Bonding
Which following structures don’t obey the octet rule?
BeCl2
BF3
H2O
Exothermic Diagram
ANS
ENDOTHERMIC DIAGRAM
ANS
What is collision theory?
The number of collisions between particles per unit time in a system
How does Pressure affect ROR?
An increase in pressure in reactions that involve gases has the same effect as an increased concentration of solutions
When the pressure is increased, the molecules have less space in which they can move
This means that the number of effective collisions increases due to an increased collision frequency
An increase in pressure therefore increases the rate of reaction
How does Conc affect ROR
The more concentrated a solution is,
the greater the number of particles in a given volume of solvent
An increase in concentration causes in an increased collision frequency
therefore an increased rate of reaction
How does Temp affect ROR?
increasing the temperature of the reaction mixture increases the rate of reaction in the following two ways:
At higher temperatures, the particles are moving faster, so collide more frequently. A higher number of collisions in total mean a higher number of successful collisions
At higher temperatures, a higher proportion of the molecules have the activation energy or more. This means that a higher proportion of collisions are successful
How does SA affect ROR?
Only the particles on the surface of a solid will collide with particles of the other reactant
If the surface area is increased, more particles will be on the surface and able to collide with particles of the other reactant
This means that there will be more collisions in total and therefore more successful collisions.
Surface area can be increased by decreasing the size of the reactant particles
For example, powders have a very large surface area
Annotate the Maxwell Boltman distribution curve?
ANNOTATION:
Annotare the Maxwell Boltman curve demonstrating an increase in Temperature?
ANNOTATION:
Annotate and explain the change in the Maxwell Boltman curve demonstrating when a catalyst is used?
Catalyst provides the reactants another pathway which has a lower activation energy
By lowering E , a greater proportion of molecules in the reaction mixture have sufficient energy for a successful collision
As a result of this, the rate of the catalysed reaction is increased compared to the uncatalyzed reaction
Catalysts can be divided into two types:
Homogeneous catalysts
Heterogeneous catalysts
Show, on a diagram, the effect of a catalyst?
HERE:
Anion Charge example?
-1
Are Energy levels for an e- further or farther apart?
farther apart near the nucleus
What does the Polarity of a molecule depend on it?
Molecules are non polar if..
- ) The molecule shape around the central atom has no lone pairs, or if it does it’s either square planer or square linear
- ) All atoms around the central atom are the same
For something to be polar, they to disobey both criterias
Distinguish between a continuous spectrum and a line spectrum.
A continuous spectrum has all colours/wavelengths/frequencies whereas
a line spectrum has only (lines of) sharp/discrete/specific colours wavelengths/frequencies;
How to tell which Molecules have IMF?
Non Polar - LDF
Polar - Dipole Dipole
Compound with HF, HN, HO
STRONGEST TO WEAKEST FORCES
Covalent, H and VDW
S W
Explain why the bonds in SiCl4 are polar but his molecule is not?
Bonds are polar as Cl more EM than Si
However, bond molecules are symmetrical, polar effect cancels out
Diagram of Sodium Iodide
Metallic Bonding
Answer
Based on the definition for rate of reaction, which units are used for a rate?
mol dm–3 time–1
Which of the quantities in the enthalpy level diagram below is (are) affected by the use of a catalyst?
Show Diagram
Exothermic Diagram
ANSWER
The graph below is Q 19 C T Kinetics Paper
Explain through rates the plateu graph?
State and explain the change in the rate of reaction with time. Outline how you would determine the rate of the reaction at a particular time.
S
When excess lumps of magnesium carbonate are added to dilute hydrochloric acid the following reaction takes place.
MgCO3(s) + 2HCl(aq) → MgCl2(aq) + CO2(g) + H2O(l)
(a) Outline two ways in which the rate of this reaction could be studied. In each case sketch a graph to show how the value of the chosen variable would change with time
BV
