Unit2Topic1 - Reactivity Series Of Metals Flashcards
Equation for metals reacting with air
metal + oxygen -> metal oxide
Equation for metals reacting with water
metal + acid -> metal hydroxide + hydrogen
Equation for metals reacting with steam
metal + steam -> metal oxide + hydrogen
Equation for metals reacting with acids
metal + acid -> salt + hydrogen
K and Na when left in air
Soft, can be cut easily with a knife to give a shiny surface that quickly tarnishes.
Ca, Mg, Al and Zn when left in air
React slowly, forming an oxide layer
Fe and Cu when left in air
Oxide layer is easily rubbed off
K when heated in air
Burns with a lilac flame
Na when heated in air
Burns with bright yellow flame
Apparatus used when heating K and Na in air
deflagrating spoon
Ca when heated in air
Burns with brick red flame
Mg when heated in air
Burns with bright white flame, leaving a white ash
Al when heated in air
Sheets of Al don’t burn easily. Powdered Al burns with white sparks, leaving white solid.
Zn when heated in air
Burns leaving yellow solid which when cooled changes to white.
Fe when heated in air
Sheets of Fe don’t burn easily. Fe wool or Fe filings burn with yellow/orange sparks, forming black solid
Cu when heated in air
Sheets of Cu quickly form black copper oxide layer. The black layer will form without heating.
Apparatus used when heating Ca, Mg, Al, Zn, Fe and Cu in air
Hold over Bunsen flame with tongs or place in crucible on a tripod over Bunsen
Reactions between metals and water are …
Exothermic: heat energy is given out and the solution warms up/ test tube feels warm.
Why do some metals have to be stored under oil? E.g. Li, Na, K
They’re very reactive with oxygen and water and are therefore stored under oil to prevent them being in contact with oxygen and moisture in the air
K reaction in water
Floats Moves rapidly around surface Bursts into lilac flame Bubbles of gas released Colourless solution formed
Na reaction in water
Floats
Moves rapidly around surface
So much heat released that Na melts into a sphere of molten metal that may burn with yellow flame
Colourless solution formed
Further tests in trough of water where K and Na have reacted
Solution changes Universal indicator from green to blue
Ca reaction in water
Ca granules will sink initially
Bubbles of gas
Beaker feels warm to touch as heat is evolved
Mg reaction in water
Very few bubbles observed even after leaving for several days
Al, Zn, Fe, Cu reactions in water
No reaction.
Fe will rust after a few days
Further tests after reacting Ca, Mg, Al, Zn, Fe and Cu in water
Gas collected in test tube burns with a squeaky pop.
Chemical formula for steam
H2O (g)
Mg reaction with steam
Reacts when heated
Produces very bright white light
White powder remains
Al reaction with steam
Al foil will not react
Small pieces will react when oxide layer is taken off
Al powder reacts when heated to form a white powder
Zn reaction with steam
Reacts when heated
Glows as steam is passed over producing a yellow powder
Yellow powder becomes white when cooled
Fe reaction with steam
Fe must be heated until it glows red before the steam is passed over
Reacts to form a black solid
Further test after reacting Mg, Al, Zn and Fe in steam
Gas burns with squeaky pop
Ca, Mg, Al, Zn reactions with acid
Bubbles of gas
Metal disappears quickly
Colourless solution formed
Test tube feels warm to the touch as heat is evolved
Rate of production of bubbles increases as you go up reactivity series
Aluminium reacting with acid
Powdered Al is used as Al oxide layer adheres to surface of Al and protects it from reaction with acid. Al foil can be used if Al oxide layer is removed with scouring pad.
Cu reaction in acid
No reaction - copper is very unreactive
Why is the reaction between zinc and dilute HCl often used to produce hydrogen gas in a school laboratory?
Zinc metal reacts with HCl and gives a steady stream of gas, not too fast, not too slow
What is a displacement reaction?
A displacement reaction is one where a more reactive element displaces a less reactive element from its compound
Reactivity series
Potassium (please) Sodium (send) Lithium (little) Calcium (Charlie's) Magnesium (monkeys) Aluminium (and) Zinc (zebras) Iron (in) Tin (tall) Lead (lead) Copper (cages) Silver (securely) Gold (guarded)
