Metals And Non-metals

Element M should belong to group 2 of the periodic table.

Reason: Since the chloride formula formed by the metal is of the form MCl₂, the valency of the metal is +2. Also, it is high melting solid so it has to be an ionic compound and so metal should be definitely from 1^st or 2^nd group. But since metals of group 1 can show only +1 valency, the metal cannot be from group 1 then it is definitely from group 2. Ex: Ca, Mg etc. are 2^nd group metals and satisfy this situation.

Mg >> Electronic configuration= 2,8,2 Stable form>> 2,8 hence valency= +2

Cl>> Electronic configuration= 2,8,7 Stable form>> 2,8,8 hence valency= -1

Formation of MgCl₂

Formation of magnesium ion by donating an electron

Mg(2,8) → Mg⁺² + 2e^-

Formation of chlorine ion by accepting an electron

Cl(2,8,7) + e^- → Cl^-

When 2 free chlorine atoms accept the electrons given by single magnesium ion the compound MgCl₂

is formed.

(a) Aluminium oxide reacts with both acidic and basic substances to give neutralization reaction and hence cannot be called a true acid as well as base. Hence it is called Amphoteric oxide.

>> Neutralisation Reaction with hydrochloric acid (behaves like a base)

>> Neutralisation reaction with Sodium hydro oxide (behaves like an acid)

(b) Ionic compounds are bound to each other with strong attraction force. Hence they are in solid form and their ions are not mobile. When in molten state the ions become mobile and act as carriers for charge and hence conduct electricity.

Cation present in MgO >>> Anion present in MgO >>>

Ionic compounds are soluble in polar solvents like water.

Aqueous solution of ionic compounds contains ions in mobile form which carry charge and hence help in conduction of electricity.

Since X loses two electrons, its valence becomes +2 and it forms the ion of the form . Similarly, valency of Y is -1 and its ionic form is .

Formation of compound with X and Y

Since compound is formed by ions it is ionic. Ionic compounds are High melting points, are soluble in aqueous solutions because of mobile ions and are soluble in water.

(a) Metals react with the things like moisture, oxygen, carbon dioxide to form a layer of substance like rust in iron which hides their shiny surface. This is what we call corrosion.

(b) Nitric acid is a strong oxidising agent and Zinc is not a very reactive metal according to the reactivity series. Hence the nitric acid oxidises the hydrogen gas which is produced may be in the first step if reaction between acid or metal had taken place. So the hydrogen gas does not evolve.

(c) Metal sulphides are insoluble in water and halides are soluble so they get washed away in spite of getting deposited over the crust.

Let us take the example of an ionic compound MgCl_2.it consists of cation . Mg in its pure form consists two extra electrons on of the other hand chlorine is sort of one electron to complete its octet. Hence one magnesium and two chlorine come together to transfer electrons between them and form the ionic compound. Formation of all ionic compounds take place in similar fashion.

Three general properties of ionic compounds are as follows:

1) Soluble in polar solvents and insoluble in organic solvents.

2) Good conductor in molten form but non-conductor in solid forms.

3) generally found in crystalline solid forms due to strong force of interaction.

(a) The most reactive metal is metal B because it can react with iron and all the metals which come below in reactive series than iron. Hence in the table, it can react with all metal sulphates except zinc sulphate.

(b) A reddish brown deposit of copper will be formed as B will react with all other metal sulphates except zinc.

(c) B>A>C>D

reason: The more reactive metal sulphates with which it can react the more reactive it is.

(d) Container of metal D will be appropriate because it doesn’t react with any of the two.

(e) Zinc sulphate can be stored in any container made from these metals because it doesn’t react with any of them.

(a) E is most reactive. Because it react with most substances.

(b) Reddish brown deposit of copper will be formed since displacement has taken place.

(c) E>B>A>C>D reason: The more it reacts the more reactive it is. Just count a number of displacements a metal will give.

(d) Container of metal D can be used for this purpose as it does not react with any of them.

(e) Aluminium and magnesium sulphates can be used to store in any container because the react with none.

Alloys are the solid mixture of two or more metals. They are made by first melting the constituent metals and then mixing them thoroughly in fixed proportions.

Brass: Made of copper and zinc

Bronze: Made of copper and tin

Solder: Made of lead and tin

(a) What is meant by corrosion? Name any two methods used for the prevention of corrosion.

The unwanted reaction of any metal with its surroundings that deteriorate its qualities is called corrosion. Two methods to prevent corrosion is Painting the metal or alloying it with some other metal in an appropriate ratio.

(b) The first step is to separate dust like and other such physical impurities from the ore. The process is called concentration of the ore. Then following steps are carried out:

First of all sulfide ores are subjected to roasting which converts them into metal oxides.

>>> Roasting(heating in excess air)

The metal oxide is then heated with carbon or coke which is a good reducing agent and converts oxide into pure metal.

>>>> Reduction with coke

The pure metal is then refined to get an ultra pure metal.

Extraction of moderate reactive metals

(a) Reema has good human values. She is a person who likes to help poor.

(b) Deficiency of metal iron in our blood causes anaemia.

(c) is the formula of folic acid.