Metals FOR NOW!!! Flashcards
What is the bonding of metals described?
Cations and delocalized electrons held together with delocalized electrons.
What is the structure of a metallic bond?
Lattice of cations surrounded by delocalized electrons.
What is an alloy?
A mixture containing at least one metal.
What are the charectaristics of alloys and are those charectaristics from mixtures or coumpounds?
- Easy to seperate (mixture)
- No fixed ratio (mixture)
- Rnge of melting points (mixtures)
- Two elements bonded (compund)
What do alloys change?
- Reactivity
- Malleablility
- Melting point
Why is it easy to replace a metal ion in a metalic bond with a different one of the same charge?
Because the electrons in a metallic bond are always moving, which causes bonds to re-arrange.
What is the malleability of mettalic bonds (one type of ionic element)?
They are malleable because the ions can move without breaking metallic bonds.
How malleable are pure metals?
Pure metals are malleable. The layers can easily slide over eachother.
How malleable are alloys?
They are less malleable than pure metals because they have differently sized atoms/ions which cause the layers to not be able to slide over eachother as easily. This is because regular lattice is disrupted.
How do metals get a full outer energy level?
They react by losing electrons to form cations.
What defines a more reactive chemical?
The less energy required to lose electrons.
Why is energy needed for metals to achieve a full outer energy level?
The energy is neede to break the electrostatic forces between outer electrons and the nucleus.
What are the reactivity rules from most important to least?
- No. of electrons lost/excluding Ag (more = more enregy)
- No. of occupied energy levels/distance between nucleus and outer energy levels (more = less energy)
- No. of protons/atomic number (more = more energy)
What metals react with water?
- Group 1
- Ca
- Sr
- Ba
- Ra
- Mg (reacts but very slowly)
Metal +water =>
metal hydroxide + hydrogen
What is the defenition of dispacement?
A more reactive element replaces a less ractive element from its compound form (compound + metal).
How does displacement work?
The more reactive element loses an electron and bonds to the compund (the electron is transferred).
What observations can be present in a displacement reaction?
- Temp. increase (greater difference in reactivity => higher temp).
- Solid changes color.
- Solution changes color.
Why are displacement reactions used?
To determine the order of reactivity because they give a posotive/negative result.
What is the defenition of extraction?
Obtaining a pure element/metal from a compound.
Why are there not many pure metals naturally?
Because pure metals react with O2/H2O over time to from compunds.
What is the reactivity series?
- K
- Na
- Li
- Ca
- Mg
- Al
- Zn
- Fe
- Cu
- Ag
- Au
Group the reactivity series into how you extract them.
- K, Na, Li, Ca, Mg, Al = electrolysis
- Zn, Fe = Displacement wit carbon
- Cu, Ag = Decomposition
- Au = No extraction needed
Metal + steam (hot water) =>
Metal oxide + hydrogen
How is the experiment for metal + steam set up?
What are the observations of Mg + O2?
- Bursts with white flame
- Produces white solid
What chameicals don’t ract with steam at all?
- Cu
- Ag
- Au
What are the observations of Zn + O2?
- Produces white solid (ZnO), but is yellow when hot.
- Burns with blue flame
- Glows red
What are the observations of Fe + H2O?
- Produces orange/brown solid
- NOT DONE WITH FLASHCAD
Why do we use carbon for displacement (reactivity series).
- Abundnat
- Produces a gaseoous oxide (easy to seperate)
Why does the metal oxide need to be a liquid in electrolysis?
Because it needs to conduct and since it is ionic, it needs to be a liquid for this to occure. High mpt :(
Draw a diagram of electrolysis.
What goes to the cathode?
The cathode (+ ion)
What goes to the anode?
The anions (- ion)
What is the defenition of an iron ore?
Haematite or iron (III) oxide (orange/brown)/siliconeoxide (sand)
What is the overall reaction of the extrction of Fe?
2Fe2O3(s) + 3C(s) => 3CO2(g) + 4Fe(s)
iron oxide and carbon react to form carbon dioxide and iron
dissplacement
What is bad about the extraction of Fe?
- Climate change
- Acid rain
What does acid rain imapct?
- Trees
- Fish
- Limestone buildings
What is the firts reaction for the extraction of Fe and the observations?
C + O => CO2
* Combustion
* Exothermic => releases heat (2000 degrease celcius)
Wha the is the second reaction for the extraction of Fe and the observations?
CO2 + C => 2CO (g) carbonmonoxide (toxic)
What is the third reaction for the extraction of for the extraction of Fe and the observations?
3CO(g) + Fe2O3 (s) => 2Fe (l) + 3CO2
* Fe is contaminated with SiO2 and will cause it to become brittle.
What is the equation for removing impurities from Fe?
CaCO3 limestone = 2000°C =decomposes=>CaO + CO2 :(
CaO base + SiO2 =neutralisation=> CaSiOcalciumsilicate (less dense than SiO2
Draw a diagram of the aparatus that extracts Fe and how it works.
Corrosion
The reaction of metals to from compounds causing their properties to change.
Metal + oxygen
=> Metal oxide
Metal + water
=> Metal hydroxide + hydrogen
Metal + acid
=> Salt + hydrogen
Iron + oxygen
=> hydrated iron (III) oxide
rust
What is the symbol for rust?
Fe3 . xH2O
When iron rusts, does the rust form a protective layer on the iron?
NO! The oxygen and water can still enter the iron underneath and can still react.
What are the ways of protecting Fe?
- Covering Fe with paint, oil or another metal<= best option
- Sacrificial protection => cover in a more reactive metak that recats instead of iron. All metals except for Zn (galvanising) are more reactive thatn Fe
What will happen to iron in a test tube with water air.
Rust
What will happen to iron in a test tube with boiled water and oil?
No rust because the oxygen is removed and the oil prevents any more from entering.
What will happen to iron in a test tube with air and CaCl2? Also what is CaCl2?
No rust because CaCl2 is anhydrous and removes the water.
What will happen to iron in a test tube with water and salt air (WaCl)
Rusts a lot because salt air is a catalyst for rusting.
