Unit 3: How do we map matter? Flashcards
1
Q
Atoms
A
- Smallest unique particle
- Nucleus + Shells
- Neutral Charge
2
Q
Nucleus
A
Centre of an atom
- Protons + Neutrons
- Positive Charge
3
Q
Protons
A
- Positively charged subatomic particle
- Present in the nucleus
- Never involved in reactions
- Number of protons = Atomic number
- Defines an element
- Mass = 1
4
Q
Neutrons
A
- Neutral (no) charge
- Present in the nucleus
- Can change (isotopes)
- Mass = 1
5
Q
Electrons
A
- Present in shells
- Negative charge
- Involved in reactions
- Mass = 0
- Can change (ions)
6
Q
Anion
A
- Negatively Charged ion
- Gained Electrons
7
Q
Cation
A
- Positively Charged ion
- Lost Electrons
8
Q
Atomic Number
A
- Number of Protons
- Defines an Element
9
Q
Atomic Mass
A
- Protons + Neutrons
- Calculating Relative Atomic Mass =
Sum of ( Abundance (%) x mass of isotope/100) for all isotopes
10
Q
Isotope
A
- Elements with varying number of neutrons
- No change in protons or electrons
- No change in charge
- Change in mass
- Naturally Occurring
11
Q
Electron Shells Configuration
A
2,8,18,32 electrons per shell (spdf)
12
Q
Metals
A
- Give Electrons (Form anions)
- Sonorous
- Lustrous
- Conductors (Heat and Electricity)
- High Melting and Boiling Point
- High Density
- Ductile & Malleable
- Opaque
13
Q
Non Metals
A
- Take Electrons (Form Cations)
- Non-Sonorous
- Dull
- Insulators (Heat and Electricity)
- Low Melting and Boiling Point
- Low Density
- Brittle - not ductile or malleable
- Transparent(relatively)
14
Q
Ore
A
Ores are naturally occurring rocks that contain metals or metal compounds in sufficient amounts to make it worthwhile extracting them. The method used to extract a given metal from its ore depends upon the reactivity of the metal and so how stable the ore is.
- Do not look like the metals they contain
15
Q
Reduction of Ores using Carbon
A
- Metals exist in ores as ‘oxides’, bonded with oxygen
- Ores are heated with carbon
- Carbon is oxidized, metal loses oxygen
16
Q
Electrolysis
A
- Ionic substances can be broken down into the elements they are made from by electricity
- For electrolysis to work, the ions must be free to move. When an ionic compound is dissolved in water, or melts the ions break free from the ionic lattice. - Electrolyte
- Positively charged particles go to the negative electrode (cathode) - metals are positively charged in ionic bonding
- Negatively charged particles go to the positive electrode (anode) - non-metals are negatively charged in ionic bonding
17
Q
Reduction using Reactivity Series
A
- Metals are arranged from most to least reactive
- More reactive metals displace lesser reactive ones in substances
18
Q
Period
A
- Row on the periodic table
- Elements in a period have same number of shells
- Atomic Radius decreases as we go from left to right on a period
- Electronegativity increases as we go left to right on a period
19
Q
Group
A
- Columns on a periodic table
- Elements in a group have the same valency (number of valence electrons in the outer shell)
- Atomic Radius increases as we go up to down on a group
- Electronegativity decreases as we go up to down on a group
20
Q
Group 1 (Alkali Metals)
A
- Alkali Metals
- 1 valence electron
- Form + cations
- Li, Na, K, Rb, Cs
- Reactivity increases as we go down
- React with water to form Metal Hydroxide + Hydrogen
- More reactive displace less reactive
- Density increases as we go down
- Boiling + Melting point decreases as we go down
- Very high boiling and melting points
- Never found as elements in nature
- Pure versions are so reactive, they are stored in oil
21
Q
Group 7 (Halogens)
A
- Halogens (Non Metals)
- 7 valence electrons
- Form - anions
- F, Cl, Br, I, At
- Reactivity decreases as we go down
- Displacement reactions with metals:
MetalCl + F = MetalF + Cl - Density increases as we go down
- Boiling + Melting Point increases as we go down
- Low Boiling and Melting Pointes
- Strong Oxidizing Agents
22
Q
Group 8 (Noble Gases)
A
- Noble Gases (Non Metals)
- 8/0 valence electrons
- Odorless, Colorless
- Stable
- Density Increases as we go down
- Boiling + Melting Point increases as we go down
- Very low boiling and melting points
- Monoatomic
- Inert
23
Q
Transition Metals
A
- Can have different valencies
- Bond in metallic bonds
- Bond in ionic bonds
- Number of valence electrons is a roman numeral after element eg: (II)
24
Q
State Symbols
A
s, g, l, aq
- Solid
- Liquid
- Gas
- Aqueous
25
Q
Limiting Reagent
A
The limiting reagent in a chemical reaction is a reactant that is totally consumed when the chemical reaction is completed.
26
Q
Electronegativity
A
- Increases along a period
- Increases up a group
- Fluorine has the highest
- An atom’s ability to attract shared electrons to itself
27
Q
Atomic Radius
A
- Decreases along a period
- Increases down a group
- Highest is Francium
28
Q
Diatomic Elements
A
- Exist naturally as two atoms (covalently bonded)
- 7 elements
- non metals
- Nitrogen
- Hydrogen
- Fluorine
- Oxygen
- Iodine
- Chlorine
- Bromine
(N H F O I Cl Br)
29
Q
Polyatomic Ions
A
- Elements bonded together that have a charge and form ionic bonds
30
Q
Galvanization
A
- The process of applying a protective zinc coating to steel or iron, to prevent rusting
31
Q
Ionization energy
A
- Energy required to remove an electron
- Alkali metals - lowest
- Increases as we move to the right (more protons in the nucleus holding electrons in)
- Increases as we move upwards (shell is closer to the nucleus)
- 2nd, 3rd…. ionization energies increase (more positive pull - nuclear charge), - how much energy is required to remove the 2nd, 3rd…. electron from the atom (working from outer shields inward.
- Affected by nuclear charge, shielding electrons and distance from nucleus.
32
Q
Electron Shielding
A
- Inner shells negative charges repel outer shells negative charges
- Shields outermost electrons from feeling full force of nuclear charge
- Nuclear charge - number of shielding electrons
