Visitors Online: 2797 | Friday 19th December 2014
CBSE Guess > Papers > Important Questions > Class XII > 2007 > Chemistry > P Block Elements
P Block Elements
1 MARK QUESTION
- Name the elements present in boranes.
- Write two uses of pyrophoric allow.
- How is orthoboric acid related to metaboric acid?
- What is inert pair effect.
- Mention an important application of silicones.
- Write one use of elemental selenium.
- Molecular nitrogen is not reactive. Explain.
- Mention an important property of hydrazine.
- Write the structure of pyrophosphoric acid.
- Water is liquid where as Hydrogen sulphide is a gas at room temperature. why.
2 MARKS QUESTION
- Explain why Boron tri chloride is monomer but anhydrous Aluminium tri chloride is dimeric.
- What is meant by 'catenation' How does the catenation tendency for elemnts of group 14 vary.
- How is that silicon atoms can have coordination number more than four but carbon atoms can not.
- What is intert pair effect. Discuss the oxidation states of Group 13 elements in relation to this effect.
- Explain why phosphorous forms penta halide whereas nitrogen cannot.
3 MARKS QUESTION
- Give the comparative account of the chemistry of carbon and silicon with regard to their:
[i] property of catenation
[ii] stability of hydrides and oxides
- Account for the following:
[i] Ammonia has higher boiling point than phosphine
[ii] Trimethyl ammine is pyramidal and trisilyl ammine is planar.
[iii] Ammonia is stronger base than phosphine.
- Describe the following about halogen family:
[i] Oxidising power
[ii] Relative strength of their hydrides
[iii] Oxyacids and their related oxidising ability
- Give reason for the following observations.
[i] Noble gases are mostly chemicallly inert
[ii] Nitrogen does not form pentahalide
[iii] Bismuth is a strong oxidising agent in pentavalent state
- [i] Discuss two similar and two dissimilar properties from the chemistry of nitrogen and that of phosphorous.
[ii] State the reason for the occurrence of diagonal relationship in the periodic table
5 MARKS QUESTION
- [A] What are silicones.
[B] COMPARE AND CONTRAST THE FOLLOWING:
- Oxidation states of tin and lead
- Structures of oxides of nitrogen and phosphorus
- Electron affinities of chlorine and fluorine
- Maximum covalency of oxygen and sulphur
- Atomic Structure and Chemical Bonding
- Solid State
- Chemical Kinetics
- P Block Elements
- D and F Block Elements
- Nuclear Chemistry
- Stereo Chemistry
- Organic Functional Group I
- Organic Functional Group II and III
- Surface Chemistry
- Chemistry In Every Day Life
- Practice Paper No.1
- Practice Paper No.2
- Practice Paper No.3
- Practice Paper No.4