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What Is the Reactivity Series? ... ​

User Ezzy
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Answer:

In a reactivity series, the most reactive element is placed at the top and the least reactive element at the bottom. More reactive metals have a greater tendency to lose electrons and form positive ions.

A reactivity series of metals could include any elements. For example,

A list of elements from most reactive to least reactive: potassium, sodium, lithium, calcium, magnesium, aluminum, zinc, iron, copper, silver, and gold.

A good way to remember the order of a reactivity series of metals is to use the first letter of each one to make up a silly sentence. For example, People Say Little Children Make A Zebra Ill Constantly Sniffing Giraffes.

Observations of the way that these elements react with water, acids, and steam enable us to put them into this series.

The tables show how the elements react with water and dilute acids:

Element Reaction with water

Potassium Violently

Sodium Very quickly

Lithium Quickly

Calcium More slowly

Element Reaction with dilute acids

Calcium Very quickly

Magnesium Quickly

Zinc More slowly

Iron More slowly than zinc

Copper Very slowly

Silver Barely reacts

Gold Does not react

Note that aluminum can be difficult to place in the correct position in the reactivity series during these experiments. This is because its protective aluminum oxide layer makes it appear to be less reactive than it really is. When this layer is removed, the observations are more reliable.

Non-metals in the reactivity series

It is useful to place carbon and hydrogen into the reactivity series because these elements can be used to extract metals.

Here is the reactivity series including carbon and hydrogen:

A list of elements from most reactive to least reactive: potassium, sodium, lithium, calcium, magnesium, aluminum, carbon, zinc, iron, hydrogen, copper, silver, and gold.

Note that zinc and iron can be displaced from their oxides using carbon but not using hydrogen. However, copper can be extracted using carbon or hydrogen. Displacement reactions of metal oxides

A more reactive metal will displace a less reactive metal from a compound. The thermite reaction is a good example of this. It is used to produce white-hot molten (liquid) iron in remote locations for welding. A lot of heat is needed to start the reaction, but then it releases an incredible amount of heat, enough to melt the iron.

aluminium + iron(III) oxide → iron + aluminium oxide

2Al + Fe2O3 → 2Fe + Al2O3

Because aluminum is more reactive than iron, it displaces iron from iron(III) oxide. The aluminum removes oxygen from the iron(III) oxide:

iron is reduced

aluminum is oxidized

Reactions between metals and metal oxides allow us to put a selection of metals into a reactivity series. Using metals A, B, and C:

Metal A Metal B Metal C

A oxide X Displaces A Displaces A

B oxide No reaction X No reaction

C oxide No reaction Displaces C X

Metal A cannot displace either B or C - so it must be the least reactive and be at the bottom of this reactivity series.

Metal B displaces both A and C - so it must be the most reactive and be at the top of this reactivity series.

Metal C displaces A but cannot displace B - so it must be more reactive than A but less reactive than B, and be in between them in this reactivity series.

In general, the greater the difference in reactivity between two metals in a displacement reaction, the greater the amount of energy released.

Aluminum is much higher than iron in the reactivity series, so the thermite reaction releases a lot of energy. Magnesium is very high in the reactivity series, and copper is very low - so the reaction between magnesium and copper oxide is more violent.

Therefore, the order is:

A list of letters from most reactive to least reactive: B, C and A,

Displacement reactions of solutions

A more reactive metal will displace a less reactive metal from a solution of one of its salts. For example:

magnesium + copper(II) sulfate → copper + magnesium sulfate

Mg(s) + CuSO4(aq) → Cu(s) + MgSO4(aq)

In this reaction, the blue color of the copper(II) sulfate fades as it is used up (magnesium sulfate solution is colorless). We would also see copper metal forming.

Reactions between metals and solutions of metal salts allow us to put a selection of metals into a reactivity series. Using metals J, K, and L:

Metal J Metal K Metal L

J sulfate X No reaction No reaction

K sulfate Displaces K X Displaces K

L sulfate Displaces L No reaction X

Metal J displaces both K and L - so it must be the most reactive and be at the top of this reactivity series.

Metal K cannot displace either J or L - so it must be the least reactive and be at the bottom of this reactivity series.

Metal L displaces K but cannot displace J - so it must be more reactive than K but less reactive than J, and be in between them in this reactivity series.

- sorry I'm late and it's is long -_-||

User Cedric Simon
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Answer:

In chemistry the reactivity series is an empirical, calculated, and structurally analytical progression of a series of metals, arranged by their "reactivity" from highest to the lowest.

User Shanmuga
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