Metals & the reactivity series
No description yet. This curated deck is ready for daily study.
Card preview (24)
what is the order of the reactivity series?
• Potassium (K) • Sodium (Na) • Lithium (Li) • Calcium (Ca) • Magnesium (Mg) • Aluminium (Al) • Carbon (C) • Zinc (Zn) • Iron (Fe) • Copper (Cu) • Silver (Ag) • Gold (Au)
How can we gauge the position of metals in the reactivity series based on their reactions with water?
• the most reactive metals will react very strongly even with water, so the metals higher in the reactivity series will have the strongest reactions • the least reactive metals will have the weakest or even no reactions with water, so the metals lower in the reactivity series will have these sorts of reactions
what is the word equation for the reaction of metals with water?
metal + water => metal hydroxide + hydrogen
How can we gauge the position of metals in the reactivity series based on their reactions with dilute hydrochloric or sulfuric acids?
• metals that are highest in the reactivity series would have already have had a strong reaction with water ∴ we know that its reaction with acid would be waaaay stronger and EXPLOSIVELY EXOTHERMIC • metals that are lowest in the reactivity series would have little/no reaction with acid
what is the word equation for the reaction of a metal with acid?
metal + acid => metal salt + hydrogen
why doesn’t a reaction occur with aluminium and acid unless the acid is concentrated or heated?
• aluminium has a protective oxide layer on its surface (caused by reacting with oxygen in the air) that prevents the aluminium beneath from reacting with the acid • concentrated or heated acid breaks down this oxide layer, allowing the aluminium to react with the acid
PRACTICAL1 - reaction of magnesium with hydrochloric acid and sulfuric acid
Mg (s) + H2SO4 (aq) => MgSO4 (aq) + H2 (g) Mg (s) + 2HCl (aq) => MgCl2 (aq) + H2 (g)
observations for the reaction of magnesium with both hydrochloric and sulfuric acid
• metal floats • metal disappears • effervescence • heat is given off
PRACTICAL2 - reaction of zinc with hydrochloric acid and sulfuric acid
Zn (s) + H2SO4 (aq) => ZnSO4 (aq) + H2 (g) Zn (s) + 2HCl (aq) => ZnCl2 (aq) + H2 (g)
observations for the reaction of zinc with both hydrochloric and sulfuric acid
rapid fizzing/effervescence
PRACTICAL3 - reaction of iron with hydrochloric acid and sulfuric acid
Fe (s) + H2SO4 (aq) => FeSO4 (aq) + H2 (g) Fe (s) + 2HCl (aq) => FeCl2 (aq) + H2 (g)
observations for the reaction of iron with both hydrochloric and sulfuric acid
a few small bubbles are formed
what do the reactions of Mg, Zn and Fe with acid tell us about their relative reactivity?
• Mg had most vigorous reaction ∴ is the most reactive • Zn’s reaction was less strong than the Mg, but stronger than the Fe ∴ is in the middle • Fe had the weakest reaction ∴ is the least reactive of the three metals
when do displacement reactions occur?
a displacement reaction occurs when a metal is reactive enough to replace another metal out of its compound
how can we tell the reactivity of a metal based on a displacement reaction of a metal with a metal oxide?
The more reactive metal (whether in a compound or as an element): - stays in the compound if already combined and the other metal is less reactive - displaces a less reactive metal from its oxide or salt solution if it’s the free element - the metal that does the displacing is more reactive; the one displaced or unable to displace is less reactive - this shows that a more reactive metal donates electrons more readily, reducing the less reactive metal’s ions or oxide
general equation for the displacement reaction of a metal and a metal oxide
More reactive metal + Metal oxide → More reactive metal oxide + Less reactive metal
how can we tell the reactivity of a metal based on a displacement reaction of a metal with aqueous solutions of metal salts?
The more reactive metal (whether in a compound or as an element): - stays in the salt solution as ions if already dissolved and the other metal is less reactive - displaces a less reactive metal from its aqueous salt solution if it’s the free element - the metal that does the displacing is more reactive; the one displaced or that doesn’t displace is less reactive - this shows that more reactive metals give up electrons more easily, reducing the less reactive metal ions to solid metal
general equation for the displacement reaction of a metal and an aqueous metal salt solution
More reactive metal + Metal salt solution → Metal salt of reactive metal + Less reactive metal
what is a reactive metal?
a metal which is more stable (i.e has a full outer shell) as an ion than as an atom ∴ reacts with other atoms to become an ion
what is an unreactive metal?
a metal which is more stable (i.e has a full outer shell) as an atom than as an ion ∴ doesn’t need to react with other atoms
name the things that must be present in order for rusting to occur
water and oxygen
what is the chemical name and formula for rust?
• name = hydrated iron (III) oxide • formula = Fe2O3.XH2O
word equation for rusting
iron + oxygen + water => hydrated iron (III) oxide
balanced symbol equation for rust formation
4Fe (s) + 3O2 (g) == H2O==> 2Fe2O3 (s)