Top 10,10th Sci.I, Metallurgy..3

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Fun of Reactivity series...🥁

@ Metals are grouped according to their reactivity 

1. Highly reactive metals. 

2. Moderately reactive metals 

3. less reactive metals.

🎺 What is meant by the reactivity series of metals ?

When metals are arranged in the increasing or decreasing order of reactivity is called the reactivity series of metals.( a list that ranks metals ). This reactivity series was derived by scientist doing many experiments of displacement reaction.

🥁 Today we will see how to extract medium reactive elements.

Extraction of moderately reactive metals.

Metals like iron Fe,  zinc Zn,  lead Pb,  copper Cu are moderately reactive elements. These metals are in the form of sulphide salts or carbonate form.

Roasting :- When sulphide ores are strongly heated in air to transform them into oxides is called roasting.

Calcination :- when carbonate ores are strongly heated in a limited supply of oxygen to transform them into oxides is called calcination.

It is easy to obtain metals from their oxides rather than sulphide or carbonate.

The zinc oxide obtained is reduced to zinc by using carbon reductant.

Reactive metals such as sodium Na, calcium Ca,  aluminium Al,  are used to reduce as reducing agents for the reduction of metal oxides to obtain the metal.

Manganese dioxide is ignited with aluminium ( as a reducing agent) powder to get manganese.

 Thermit reaction :- the reaction in which heat is evolved so that the metal is formed in a molten state that reaction is called thermit reaction.

When iron oxide reacts with aluminium to form iron and Aluminium oxide this is an exothermic reaction.

Extraction of less reactive metals.

Metals like copper Cu, silver Ag,  gold Au ,  platinum Pt are extremely less reactive, and found in free state in nature.

These metals are located at the bottom of the reactivity series.

Cuprous(1) sulphide when heated in air we get copper.

Refining of metals :-

The metals which we get from the reduction process are not very pure they contain impurities (carbon C , sulphur S ) . To obtain a pure metal electrolysis method is used.

In IX Science Textbook Page No. 56   , If we approach well, means learn radicals properly we can solve chemical reactions easily.

Today we are going to look at some of the chemical reactions in this lesson.

Sodium and potassium metal react rapidly and vigorously with water in this process hydrogen gas is liberated.

Calcium reacts with water slowly and the hydrogen gas released in this process gets collected on the surface of calcium due to which metal Ca floats on water.

Aluminium Al,  iron Fe and zinc  Zn do not react with cold water or hot water. They react with steam to form metal oxides , hydrogen gas is also liberated in this process.

Metals react with dilute acid to form metal salt and hydrogen gas is liberated

Some metals react with nitric acid .When copper react with concentrated nitric acid copper nitrate is formed in this process nitrogen dioxide is liberated.

Copper reacts with dilute nitric acid to form copper nitrate and nitric oxide NO  liberate.

बोलण्यासारखं बरंच काही असताना देखील "स्मित हास्य" करून वेळेवर विषय हाताळणे यालाच कदाचित "अनुभव" म्हणतात...* 

*आपला दिवस आनंदी जावो.*