Module 2// Foundations in chemistry Flashcards Preview

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Flashcards in Module 2// Foundations in chemistry Deck (16)
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1
Q

what is the difference between atom economy and percentage yield?

A

Atom economy is the percentage of products of a reaction that successfully converted to the desired product
Whereas percentage yield is how much product was lost in the reaction

2
Q

Give 3 reasons why the percentage yield is not 100%

A
  • reversible reaction
  • product lost in transfer
  • reactants not used up
3
Q

electron configuration

A

A shorthand representation that shows how electrons occupy sub-shells in an atom

4
Q

Shells (aka energy levels)

A

A group of atomic orbitals w the same principle quantum number= n

5
Q

What are shells divided up into?

A

Shells are divided up into sub-shells (s-,p-,d-,f-)

6
Q

Sub-shell

A

A group of orbitals of the same type within a shell

7
Q

Atomic orbital

A

A region around the nucleus that can hold up to 2 electrons w OPPOSITE spins

8
Q

What is meant by the term ‘spin’ in an atomic orbital

A

The 2 electrons that occupy an orbital must spin in opposite directions
= Aka SPIN-PAIRING

9
Q

Up to how many electrons can s-orbitals hold

A

s-orbitals can hold up to 2 e-

10
Q

Up to how many electrons can p- orbitals hold

A

p-orbitals can hold up to 6 e-

11
Q

Up to how many electrons can d-orbitals hold

A

d-orbitals can hold up to 10 e-

12
Q

Up to how many electrons can f- orbitals hold

A

f-orbitals can hold up to 14 e-

13
Q

Why are orbitals within sub-shells occupied singly first

A

Orbitals within sub-shells are occupied singly first because orbitals within a sub-shell have the same energy

1e- occupies each orbital before pairing starts— this prevents any repulsion between paired e- until there is no further orbital available at same energy level

14
Q

relative isotopic mass

A

The mass of an atom of an isotope compared with 1/12th of the mass of an atom of carbon 12

15
Q

relative atomic mass

A

the weighted mean mass of an atom of an element compared with 1/12th of the mass of an atom of carbon 12

16
Q

amount of substance

A

the quantity whose unit is the mole, used as a means of counting any species such as atoms, ions + molecules