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Model Test Questions XII Chemistry Chapter # 1 Chemistry of Representative Elements

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Short Question Answers from Textbook


1. Give reason for the following:

▶ Ionization energy decreases from top to bottom in s-block elements.

▶ Boiling points of halogens increase down the group in the periodic table.

▶ Gallium has smaller atomic radii than aluminium despite being below the aluminium in group IIIA.

▶ Electronegativities of alkali metals decrease from Li to Cs.

▶ Acidity of hydrogen halides increase from HF to HI.

▶ Fluorine is the strongest oxidizing agent.

 

2. What is flame test? Mention the colour flame of alkali metals.

 

3. What is meant by a diagonal relationship? Mention three pairs of representative elements that show diagonal relationship.

 

4. Discus the group trend of ionization energy in group IIIA and IVA of the periodic table.

 

5. Write down four properties of beryllium that show its unique behaviour in group IIA.

 

Short Question Answers from Past Papers 


Q1. Write down three points to show the similarity of diagonal members of group IA and IIA, IIA and IIIA and IIIA and IVA.

 

Q2. What is the basis of flame test?  Mention the colour flame of alkaline earth metals.

 

Q3. Discus the group trend of atomic radii in group IIIA of the periodic table

 

Q4. What is Electrical conductivity? Briefly explain group trend of electrical conductivity of representative Elements

 

Q5. Write down action of oxygen and water on s-block elements with balanced chemical equation.

 

Q6. Complete and balance the following chemical equations: 


















Descriptive Questions


Q1. Discuss the group trend of atomic radii, melting and boiling points, oxidation states and electronegativity of representative elements.
















Short Question Answers from Past Papers 







 












Answer of Descriptive Questions











 Extra Questions 

 






























































































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