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. The reactivity series In a reactivity series, the most reactive element is placed at the top and the least reactive element at the bottom. For example: 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.
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 aluminium can be difficult to place in the correct position in the reactivity series during these experiments.
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: Note that zinc and iron can be displaced from their oxides using carbon but not using hydrogen. Very quickly. Thus, cesium is the most reactive metal on the periodic table.
In general, the alkali metals are the most reactive, followed by the alkaline earths and transition metals. The noble metals silver, platinum, gold are not very reactive. The alkali metals, barium, radium, strontium, and calcium are sufficiently reactive that they react with cold water.
Magnesium reacts slowly with cold water, but quickly with boiling water or acids. Beryllium and aluminum react with steam and acids. Titanium only reacts with the concentrated mineral acids. The majority of transition metals react with acids, but generally not with steam.
The noble metals only react with strong oxidizers, such as aqua regia. In summary, moving from the top to the bottom of the reactivity series, the following trends become apparent:. The three types of reactions used to test reactivity are reaction with cold water, reaction with acid, and single displacement reactions. The most reactive metals react with cold water to yield the metal hydroxide and hydrogen gas.
Reactive metals react with acids to yield the metal salt and hydrogen. Metals that do not react in water may react in acid. When metal reactivity is to be directly compared, a single displacement reaction serves the purpose.
A metal will displace any metal lower in the series. For example, when an iron nail is placed in a copper sulfate solution, iron is converted to iron II sulfate, while copper metal forms on the nail. The iron reduces and displaces the copper.
The reactivity of metals may also be predicted by reversing the order of standard electrode potentials. This ordering is called the electrochemical series. The electrochemical series is also the same as the reverse order of the ionization energies of elements in their gas phase.
The order is:. White solid formed. Slowly forms a surface oxide at room temperature No reaction Reacts as a powder on strong heating. Yellow solid forms which changes to white on cooling. Orange sparks and black solid formed.
Slowly forms a surface oxide at room temperature No reaction Reacts as a powder on very strong heating. Black solid formed. Slowly forms a surface oxide at room temperature No reaction No reaction Least reactive Prescribed Practical C5 - Investigate the reactivity of metals. Potassium K. Reacts vigorous when heated. Tarnishes when freshly cut at room temperature.
Reacts vigorously. Most reactive. Sodium Na. Reacts vigorously when heated. Calcium Ca. Reacts vigorously with strong heating. Slowly forms a surface oxide at room temperature. Reacts readily. Magnesium Mg. Reacts readily with strong heating.
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