Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

CHEMISTRY > chemistry key concepts > Flashcards

chemistry key concepts Flashcards

1
Q

what is the atomic number

A

the number of protons in the nucleus of that element

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the number of protons always equal to

A

the number of electrons in an atom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

why is an atom neutral/ no charge

A

because the number of protons is equal to the number of electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what charge do protons have

A

positive charge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what charge to electrons have

A

negative charge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the equation for atomic mass

A

number of protons + number of neutrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

which number is the mass number

A

the bigger number

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

which number is the atomic number

A

the smaller number

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what do you use to draw the electron structure

A

atomic number

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is an isotope

A

an atom of the same element, with the same number of prons and electrons but different neutron number

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the relative atomic mass

A

an average of the mass number of all of the isotopes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

wha is the equation for relative atimic mass

A

(percentage abundence x atomic mass) + ( percentage abundance x atomic mass) / percemtahe abundance + percentage abundence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is the plum pudding model

A

a ball of positive charge with negative electrons scattered in it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

who theroised the plum pudding model

A

JJ thompson

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what did Chadwick discover

A

neutrons and what isotopes are

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

when new evidinece comes up, what happens to the model

A

it changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what does the scatter expeiment discover

A

the nuclear model

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what happened during the scattering experiment

A

atom particles were fired at a golf leaf

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what were three observations from the scattering experiment

A
  1. most of the alpjas particles went straight through the atom and meant most of the atom was empty space
  2. some of the alpha particles were deflected back and it meant that the mass of the atom was concentrated in a tiny area in the centre of the nucleus
  3. some of the alphas particles were deflected slightly from the particles and that meant the positive charge was not spread out but found in the nucleus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what did bohr theorise

A

electrons are found in energy levels at specific distance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what are three diffrences from nuclear model and the plum pudding model

A
  1. in the nuclear model the positive charge is in the nucleus. whereas in the plum pudding model the atom is a ball of positive charge
  2. in the nuclear model the atom is mostly empty. contrastingly, in the plum pudding model the atom has no empty
  3. in the nuclear model, the mass of the atom is concentrated in the nucleus. opposingly in the plum pudding model the mass is spread out
22
Q

how is the periodic table arranged

A

in accordance with the atomic number which is the number of protons and protons weren’t discovered till later

23
Q

how many elementss were there when mendeelev organised the periodic table

A

63 elements

24
Q

how did Mendeleev arrange the elements

A

accoding to the atomic weight and their propoertires

25
Q

whike he was organising the periodic table, he concluded that some elements were undiscoverd why

A

some of the elements did not fit in the pattern and left gaps to fix the problems

26
Q

why did Mendelev swap the positions of some elements

A

for them to fit in the pattern

27
Q

what were elements put into groups based on

A

the number of electrons they have in their outershell

28
Q

what were the elements put into periods based on

A

the number of shells they have

29
Q

whagt is the same word as energy levels

A

shells

30
Q

what are the periods on the periodic tabl

A

rows

31
Q

what are the groups in the periodic table

A

collums

32
Q

what was daltons model

A

very tiny solid indivisible sphere

33
Q

what are the three subatomic particles

A

protons, electrons and neutrons

34
Q

were there any subatomic particles in the daltons model

A

no

35
Q

description of the structure of the atom

A
  1. made up of prtons, neutrons and electrons
  2. protons and neutrons are found in the nucleus of the atoms
  3. electrons are on the shell/ energy level
  4. protons are positive charge
  5. electron is negative charge
  6. neutrons have no charge
  7. protons and neutrons have a mass of 1
  8. electrons have a mass of 1/2000 ( negligible - too small, we can ignore it )
36
Q

what is relative formula mass

A

yhe sum of the relative atomic masses of all the elements shown in a chemical formula

37
Q

what is the law of conservation of mass

A

the mass of the products in a chemical reaction must be equal to the mass of the reactants

38
Q

what is concentration

A

a measure of how much of a soluble siinstamce os dissolved in a substance

39
Q

wjat is concentration measure in

A

g/dm^3

40
Q

what is the equation for concentration

A

mass/volume

41
Q

how do you convert cm^3 to dm^3

A

divide by 1000

42
Q

how do you convert dm^3 to cm^3

A

times by 1000

43
Q

what is the the size of an atom

A

1 x10^-10

44
Q

what is the size of the nucleus of an atom

A

1x10^-14

45
Q

what is avagadros number

A

the number of atoms in one mole of any substance

46
Q

what is the equation to calculate moles

A

mass/mr

47
Q

what is avogadros constant

A

6x10^23

48
Q

small -> big

A

times

49
Q

big to small

A

divide

50
Q

what is empricial formula

A

when you divide by the smallest number

CHEMISTRY (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions