Periodicity + Bonding + Calculations Flashcards
Electrons are LEPTONS but which fundamental particles make up protons + neutrons?
Up and down quarks!
Which electrons are used in forming bonds?
Electrons in the OUTERMOST subshell of electrons! (Valence electrons)
P orbitals are shaped as…
3 - three dimensional hour glasses
We can demonstrate that a mole contains 6.02x10^23 atoms or molecules because…
We can measure the charge on 1 mole of electrons
Atomic radius…
DECREASES across a period - nuclear charge increases with NO new layers of electrons shielding.
Increases down group - new layers of electrons are shielding valence shells from nuclear charge!
Ionic bond is strong because
Electrostatic Attraction between ALL ions in the lattice!
A dative Covent bond is important in…
Keeping Iron in Haemoglobin
Electronegativity AND Ionisation Energy…
Increases across a period - nuclear charge increased, NO additional shielding electrons so nuclear charge has GREATER influence over outer electrons!
DECREASES DOWN GROUP - new layers of shielding electrons DECREASE influence of nuclear charge on valence (outer shell) electrons!
One mole of substance contains how many atoms or molecules?
6.02 x10^23
One Mole of sodium would weigh how much?
23g - just it’s mass number!
One mole of potassium chloride KCL would weigh how much?
- Find mass number (larger one) of K and all and then ADD them! *
39 + 35.5 = 74.5g
To make a solution one mole/l how many moles would I add to 0.5l of solvent?
1 mole = 1 litre
so…
0.5 litre = 0.5 mole
How much Calcium Carbonate CaCO3 would I need to add 0.1 litre of water to make a solution of 0.5 mole/l?
Find MR of CaCO3 first!
Ca = 40 / C = 12 / O = 16. Total= 100.
Moles = concentration x volume
0.5 x 0.1 = 0.05 moles.
Mass = moles x Mr
0.05 x 100 = 5g!!!
C1 x V1 = C2 x V2.
If the volume of 0.3M potassium permanganate added was 500ml and the volume of water added was 500ml what was the FINAL CONCENTRATION of potassium permanganate?
C2 = C1 x V1 divided by V2.
TOTAL volume = 500 + 500 = 1000ml.
0.3 x 500 divided by 1000
= 0.15!
How to convert ml to Ul?
Ml x1000 = ul
How to convert L to ml?
L x1000 = ml
If you ADD 100ul to 0.5M solution to 400ul water. What is the final concentration?
C(initial) x V(ADDED to tube) = C (final) x V(final)
- 5 x 100 divided by 500 = 0.1M.
* Don’t need to convert units as they are the same!
* Remember total volume is 400 + 100!
CONCENTRATION VALUES
1M = 1 mole per litre
1mM = 1 millimole per litre
1um = 1 micromole per litre!
The subatomic particles found in atoms consist of which fundamental particles?
Quarks
Leptons
What BEST describes an electron?
Electrons are leptons and found in a PAIRED state with one up and one down electron
