Vsepr theory, hybridization and VBT

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Rutherford's alpha Particle scattering experiment : Discovery of nucleus

Alpha particle:

Alpha particle is helium nucleus having 2 unit positive charge and 4 unit mass. Radioactive substances emit alpha particles continuously as alpha rays,

  Experimental setup:

A thin gold foil is taken and encircled by zinc suphide screen, Alpha particle is generated inside a lead box, A thin beam of alpha ray is passed on gold foil through a narrow slit. When alpha particles hit on gold foil, scattering occurs.

Scattered particles hit on zinc sulphide screen and produce flashes on the screen. it is observed by a microscope.  

Observations, conclusions and Ruthermord's  atomic model.

For the detailed study of observations, conclusions and Ruthermord's  atomic model,  watch on youtube. 

Thomson's atomic model

  After the discovery of electrons, J. J. Thomson put forwarded the atomic model to describe the occurrence of electrons inside the atom. He considered electrons are scattered inside the atom as seeds are scattered inside the watermelon. Electrons are negatively charged particles. The positive charge diffused on the atom neutralizes the negative charges of electrons. That's why it is called the watermelon model of the atom.

sigma and pi bonds

 sigma and pi bonds are two types of covalent bonds. They differ each other on the mode of overlapping of atomic orbitals- head to head overlapping or sidewise overlapping. The first kind of overlapping gives a sigma bond while the second kind of overlapping gives a pi bond.

Click here to watch the video on youtube   

Indian Variant cases are conformed in Nepal

 Out of 35 samples sent in Indian laboratory, 34 samples are conformed as Indian variant because their gene sequence match with Indian variant. Indian variant is that which is taken as variant of concerned by WHO. It easily affects all age groups and transmits rapidly.                        Stay safe            

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Common names of organic compounds

 Important organic compounds and their common names

S.N.	Structural formula  of Organic compound  (or group)	Common name	IUPAC name	Remarks
		n-propyl group
		Iso-propyl group
	CH3-CH2-CH2-Cl	n-propyl chloride	1-chloropropane
	CH3-CH2-CH2-OH	n-propyl alcohol	Propan-1-ol
		Iso-propyl chloride	2-chloropropane
		Iso-propyl alcohol	Propan-2-ol
		n-butyl group
		iso-butyl group
		sec-butyl group
		tert- butyl group
	CH3-CH2-CH2-CH2-Cl	n-butylchloride
		isobutylchloride	1-chloro-2-methylpropane
		sec. butylchloride	2-chlorobutane
		tert. butylchloride	2-chloro-2-methylpropane
	CCl4	Carbontetrachloride	Tetrachloromethane
	CHCl3	Chloroform	Trichloromethane
	CHI3	Iodoform
	CH3-CN	Methyl cynide	Ethane nitrile
	COCl2                       OR	Phosgene     Or  carbonyl chloride
	CCl3-CHO	Chloral	1,1,1-trichloroethanal
	CCl3-NO2	Chloropicrin         or Nitrochloroform	Trichloronitromethane
		Vic. dichloride          (vicinal dichloride)		If two halogen on adjacent carbon   'vic' is used
		Gem. dichloride    (germinal dichloride)		If two halogen on same carbon atom  'gem' is used
		Ethylene glycol	Ethan-1,2-diol
	OHC-CHO         or	Glyoxal	Ethandial
		cynohydrin		Having -OH & -CN group on same carbon
		Acetonecynohydrin		As it is obtained from acetone
	NH2OH	Hydroxyl amine
		oxime
	NH2-NH2	Hydrazine
		hydrazone
	NH2-NH-CO-NH2	Semicarbazide
		semocarbazone
	or	Benzene
		Nephthalene
	or    C6H5-	Pheny group
		Diphenyl or Biphenyl
		Diphenyl ether
		Phenol
		Toluene
		Aniline
		Nitrobenzene
		Benzaldehyde
		Benzoic acid
		o-Xylene
		o-cresol	o-hydroxytoluene	What is  m-cresol?
		Salicyaldehyde	o-hydroxy benzaldehyde
		Salicylic acid	o-hydroxybenzoic acid
		Benzyl group
		Benzal group
		Benzo group
		Benzoyl group
		Benzyl chloride		Write benzyl alcohol
		Benzalchloride		What is benzal alcohol
		Benzotrichloride		What is benzotriol?
		Benzoyl chloride
		o-chlorotoluene
		o-tolunic acid		Write m-toluenic acid
		Acetophenon
		Benzophenon
		Benzamide
		Anisol	Methoxy benzene