Metals Flashcards
(Metal) atoms are closely packed and arranged in orderly layers of (__) atoms. The layers of (__) atoms can slide over each other easily.
Hence (metal) is __________ (property)?
Hence (metal) is malleable and can be beaten into shape without breaking.
Hence (metal) is ductile and can be pulled into wires without breaking.
(Metal) atoms are closely packed and arranged in orderly layers of (__) atoms.
Hence (metal) has __________ (property)?
Hence (metal) has a high density since the mass of (__) atoms per unit volume is high.
Why do metals have high melting and boiling points?
Metals have a metallic structure with strong metallic bonds between the (__) ions and the sea of delocalised electrons. A lot of energy is needed to break these bonds. Hence (__) has a high melting and boiling point.
Why can metals conduct heat and electricity?
Metals have a metallic structure with strong metallic bonds between the (__) ions and the sea of delocalised electrons.
The mobile electrons can easily collide with other particles, making heat transfer efficient.
OR
The mobile electrons are able to act as charge carriers to conduct electricity.
Alloys are weaker than their constituent metals. True or false?
False. They are stronger.
Alloys are harder than their constituent metals. True or false?
True. They are less malleable because they are stronger.
What makes alloys harder than their constituent metals?
In an alloy, the atoms of the different metals / elements have different atomic radii. The (smaller percentage / non metal element) atoms disrupt the orderly arrangement of the layers of (main metal) atoms.
The atoms of different sizes cannot slide over each other easily when a force is applied. Hence, the alloy is stronger than (pure metal).
Where is aluminium in the reactivity list?
Below Magnesium, above Zinc
Why does aluminium sometimes behave like the unreactive metals?
There is a protective layer of aluminium oxide that naturally coats the metal.
Is Tin or Zinc more reactive?
Zinc
Does copper react with oxygen?
Yes
Which metals can react with cold water?
Potassium, Sodium, Calcium, Magnesium (very slowly)
Which metals can react with water?
K - Mg: Cold water (produce hydroxide)
Mg - Fe: Steam (produce oxide)
Which metals react with Oxygen?
K - Hg
Which metals react with acid?
K - Pb
for tin and lead, they react very slowly
More reactive metals form more/less stable ions?
More stable ions
Will the ions of more reactive metals react / decompose more easily?
No. They are more stable, so they react / decompose less easily.
Less reactive metals form more/less stable ions?
Less stable ions.
Will less stable ions react / decompose more easily?
Yes
What is a metal displacement reaction?
A reaction where a more reactive metal displaces the ions of a less reactive metal from its aqueous salt.
Why do metal displacement reactions happen?
A more reactive metal has a higher tendency to lose its valence electrons to form a more stable ion. Hence it will donate its electrons to the metal ions of the less reactive metal.
Why is a more reactive metal a stronger reducing agent?
A reducing agent donates electrons to other substances. Since a more reactive metal has a higher tendency to lose electrons than a less reactive metal, it is a stronger reducing agent.
What is a thermite reaction?
A type of metal displacement reaction where the more reactive metal displaces the ions of the less reactive metal from its solid metal oxide.
A lot of heat is generated in the process. (energy needed to break bonds < energy given out when bonds are formed)
What is an application of a thermite reaction?
Melt railways tracks to mend broken tracks.
What is an example of thermite reaction?
2Al (s) + Fe2O3 (s) –> Al2O3 (s) + 2Fe (s)
The more stable the element, the less stable the compound. True or false?
False. The more stable the element, the more stable the compound.
Why do the Hg-Pt oxides decompose on heating but not the other oxides?
Mercury, Silver, Gold and Platinum are less reactive than the rest of the metals in the reactivity series. The ionic bonds in the oxides of Hg-Pt are not as strong as that in the more reactive metals. Hence, they are less stable and are more likely to decompose on heating.
Very stable ions form unstable or stable compounds?
Stable (strong ionic bonds within the compound)
The oxides of Potassium to Aluminium are not reduced by hydrogen and carbon. Why?
K-Al are very reactive metals that lose valence e- readily to form stable ions. These ions form compounds with a strong ionic bond that cannot be broken by hydrogen and carbon. Hydrogen and carbon are not reactive enough to reduce the metal ions to metal atoms.
For metal oxides, which ones will decompose on heating?
Hg - Pt
Give metal and oxygen.
Does every metal have a metal oxide?
Yes
What is the action of hydrogen on metal oxides?
For K-Zn, no reaction
For Fe-Pt, reduced to metal