Chemical properties of Non- metals class 8 contains a detailed explanation of chemical reactions of non-metals. Non-metals are electro -negative elements which have tendency to gain electrons to complete their octet. They are located at right side of the periodic table.
In this article, we are going to discuss chemical properties of non-metals class 8 in detail. Actually, we will go through chemical reactions of non metals that show their reactivity.
Chemical Properties of Non-Metals for Class 8
Chemical properties of non-metals include following chemical reactions.
- Reaction of non-metals with oxygen
- Reaction of non- metals with water
- Reaction of non-metals with acids
- Reaction of non-metals with bases
- Reaction of non-metals with salt solutions
Reaction of non-metals with oxygen
Non-metals react with oxygen to form non-metal oxides and these oxides are acidic nature.
i. Reaction of Sulphur with oxygen: When Sulphur burns in the presence of air, it combines with oxygen to form Sulphur dioxide.
`S + O_2 →SO _2`
ii. Reaction of carbon with oxygen: Carbon reacts with excess of oxygen to form carbon dioxide which is acidic in nature.
`C+ O_2 → CO_2`
When carbon reacts with insufficient oxygen to form carbon monoxide.
` 2C+ O_2 →2CO`
iii. Reaction of phosphorus with oxygen : Phosphorous reacts with oxygen to form phosphorous pentaoxide.
`4P+ 5O_2 → 2P_2O_5`
iv. Reaction of hydrogen with oxygen : It produces water.
`2H_2 + O_2 →2H_2O`
v. Reaction of chlorine with oxygen : Chlorine reacts with oxygen to form chlorine dioxide.
`Cl_2 + O_2 → 2ClO_2`
Reaction of non-metals with water
Non – metals do not react with water because they have different electronic configuration and have tendency to gain electrons, so they are less reactive.
Reaction of non-metals with acids
Non – metals do not displace hydrogen from acids so they do not react with acids. Non metals are electronegative elements and they do not donate electrons, so they do not react with acids.
But reaction between non-metal and concentrated acids takes place on heating
`S +2 H_2SO_4 \overset{heat}{\rightarrow}3SO_2 + 2H_2O`
Reaction of non-metals with bases
Some metals react with alkali that are water soluble bases. NaOH, KOH are alkalis.
i. Reaction of chlorine with sodium hydroxide : Chlorine reacts with sodium hydroxide to form sodium hypochlorite.
`Cl_2 + 2NaOH \overset{heat}{\rightarrow} NaOCl + NaCl + H_2O`
ii. Reaction of phosphorous with sodium hydroxide : Phosphorous reacts with aqueous sodium hydroxide to form sodium hypophosphite and phosphine gas.
`P4 + 3NaOH + 3H_2O →3NaH_2PO_2 + PH_3`
Reaction of non-metals with salt solutions
More reactive non-metal displaces a less reactive non- metal form its salt solution. The reaction is displacement reaction.
`2NaBr(aq) + Cl_2(g) → 2NaCl + Br_2`
In this reaction, when chlorine gas is passed through a solution of sodium bromide then sodium chloride and bromine are formed.
Reaction of non-metals with metals
Metals are electro positive and non-metals are electro negative elements. Metals donate or loss electrons form their outermost shell while non-metals gain or accept electrons in their valene shell.
When a metal reacts with a non-metal, transfer of electrons takes place and ionic compounds are formed
`Na → Na^+ + e^-`
`Cl + e- → Cl-`
`Na+ + Cl- → NaCl`
Important Questions
1.Name the products when Sulphur reacts with oxygen.
Ans – Sulphur dioxide (SO2) is formed when Sulphur reacts with oxygen.
2.What is the nature of Sulphur dioxide?
Ans- Sulphur dioxide is acidic in nature.
3.Why are non-metal oxides acidic in nature?
Ans – Non-metal oxides react with water to form acidic solutions so they are known to be acidic in nature.
4.Give a balanced chemical equation for the reaction of carbon with excess of oxygen.
Ans – `C + O_2 →CO_2`
5.What is the product when carbon reacts with insufficient oxygen?
Ans- Carbon monoxide
6.What substance is formed when phosphorous reacts with oxygen?
Ans- Phosphorous penta oxide `P_2O_5`
7.Why do non-metals not react with water?
Ans – Non-metals are electronegative and they accept electrons. So they are less reactive, that’s why they do not react with water.
8. What type of compounds are formed when metals react with non-metals?
Ans- They form ionic compounds because they exchange electrons.
9.Write the balanced chemical equation of reaction of `Cl_2` with NaOH.
Ans- `Cl_2 + 2NaOH \overset{heat}{\rightarrow} NaOCl + NaCl + H_2O`
10.Name the non- metal which reacts with sodium hydroxide to form sodium hypophosphite.
Ans- Phosphorous
11.What is the reaction called when a more reactive element displaces a less reactive elements from its solution?
Ans – Displacement reaction
12.What chemical reaction occurs when non metal reacts with oxygen?
Ans- When non -metal reacts with oxygen, they undergo oxidation reaction to form non-metal oxides.
13.What compound is formed when chlorine reacts with oxygen?
Ans – Chlorine dioxide is formed when chlorine reacts with oxygen.
14.Can nonmetal dissolve in water?
Ans – Yes, some non-metals like hydrogen, oxygen, nitrogen dissolve in water to some extent.
15.Why is oxygen called a non metal?
Ans – Oxygen is electronegative element and it has tendency of accepting electrons , so oxygen is called a non-metal.
16.What is the nature of non-metal oxide?
Ans – Non-metal oxide is acidic in nature.
Related Topics
FAQs
1.With the help of equations explain the reaction of non-metals with oxygen.
Ans- Non-metals + oxygen Non-metal oxide
`C+ O2 →CO_2`
2.What are chemical properties of non-metals?
Ans – Non-metals reacts
- with oxygen to form non-metal oxides
- does not react with water.
- With metals to form ionic compounds.
- Does not react with acids.
3.Can non-metals reacts with metals?
Ans – Yes, non-metals react with metals to form ionic compounds.
4.How do non-metals react with metals?
Ans- Non metals reacts with metals by accepting electrons form metals.