Brainscape's Knowledge GenomeTM

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


See full index

chemistry > atomic structure and the periodic table > Flashcards

atomic structure and the periodic table Flashcards

1
Q

how big is an atom

A

generally, atoms have a radius of around 0.1 nm

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

what is an isotope

A

different forms of the same element that have the same number of protons but a different number of neutrons

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

how do you find the relative atomic mass of an element

A

sum of (isotope abundance x isotope mass) / sum of abundances of all isotopes

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

what is a molecule

A

a group of 2 or more atoms held together by chemical bonds

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

what is a compound

A

substances that contain 2 or more different elements held together by chemical bonds

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

what is a mixture

A

two or more substances that are not chemically combined together

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

what is filtration

A

a separation technique that can separate an insoluble solid from a liquid

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

how can you separate a soluble solid from a liquid

A

either by evaporation or crystallisation

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

what are the advantages and disadvantages of evaporation

A
  • quick and easy

- however some solids decompose when heated

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

when is distillation used

A

when you need to separate mixtures that contain liquids

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

what equipment is used during distillation

A
  • flask
  • bung
  • thermometer
  • condenser
  • water jacket
  • beaker
  • bunsen burner
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are the steps of simple distillation

A
  • heat the solution until it reaches the boiling point of the liquid you want to separate
  • the gas particles will condense in the condenser due to the cold water
  • the liquid will then drip out into the beaker
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is a fractionating column

A

a tall container containing little glass rods, used during fractional distillation

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

what is the atomic theory

A

the theory that everything is made of tiny particles that can’t be broken down any further

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

what was john dalton’s theory about the atom (1800s)

A

dalton believed that atoms were solid sphere and that different types of spheres might make different elements

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

what was jj thompson’s theory (1897)

A

plum pudding model

  • believed that atoms could not be solid spheres
  • they were instead general balls of positive charge with discrete electrons in it
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what experiment did ernest rutherford and his students carry out in 1909

A

they fired positively charged alpha particles at a thin sheet of gold

  • if thompson’s theory was correct all the particles should have gone straight through
  • however some particles were deflected partially and others directly sent backwards
18
Q

what was rutherford’s theory about the atom

A

atomic model theory

  • compact nucleus with all the positive charge
  • negative charge in some sort of cloud
19
Q

what was niels bohr’s idea

A
  • negatively charged electrons orbited the nucleus

- electrons held in shells

20
Q

who provided evidence for the existence of neutrons

A

james chadwick

21
Q

what do atoms need to be stable

A

a full outer shell

22
Q

what was dimitri mendeleev’s periodic table like

A
  • arrange in order of increasing atomic number (number of protons)
  • grouped with elements that had similar properties
  • left spaces for undiscovered elements
23
Q

why do elements in the same group have similar properties

A

they have the same number of electrons in their outermost shell which is what largely determines how an element reacts

24
Q

why do metals become more reactive as you go down the group

A

the number of shells increases, meaning there is a greater distance between the outermost shell and the nucleus making it easier for the atom to lose electrons as the nucleus cannot hold onto them strongly

25
Q

what are the physical properties of metal

A
  • metallic bonding
  • malleable
  • great conductors of heat and electricity
  • high melting and boiling points
26
Q

what are the physical properties of non-metals

A
  • dull in colour
  • brittle
  • low melting and boiling points
  • lower density
  • bad conductors
27
Q

what are the properties of transition metals

A

typical metal properties plus:

  • can form more than one ion
  • often colourful
  • very good catalysts
28
Q

what are group 1 elements called

A

alkali metals

29
Q

what are the properties of the alkali metals

A
  • very reactive
  • soft
  • low density
  • low melting point
30
Q

what is the trend as you go down the group 1 metals

A
  • melting point and boiling points decrease

- more reactive

31
Q

why are alkali metals so reactive

A

they only have 1 electron in their outermost shell, which is easy to lose to form a stable ion

32
Q

what type of compounds do alkali metals generally form

A

white solids that dissolve in water to form a colourless solution

33
Q

what metal oxide does lithium form

A

litium oxide

34
Q

which metal oxides does sodium form

A

sodium oxide or sodium peroxide

35
Q

which metal oxides does potassium form

A

potassium peroxide and potassium superoxide

36
Q

what are the group 7 gases known as

A

halogens

37
Q

describe what the elements in group 7 are like

A

fluorine - poisonous, yellow gas which is very reactive
chlorine - less reactive poisonous, green gas
bromine - red/brown volatile liquid which is also poisonous
iodine - dark-grey solid that can form poisonous purple vapours also antiseptic

38
Q

in what type of molecules do the halogens exist as

A

diatomic molecules

39
Q

what are the trends as you go down group 7

A
  • melting and boiling point increase

- reactivity decreases

40
Q

why does reactivity decrease as you go down the table

A

atomic radius increases, so the attractive force that is needed to pull in electrons weakens

41
Q

what are group 0 elements known as

A

noble gases

42
Q

what are the properties of noble gases

A
  • all exist as colourless gases
  • full outer shells so they don’t really react with anything (inert)
  • non-flammable

chemistry (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions