Name the parameters that characterize a unit cell.
A unit cell is the smallest repeating unit in space lattice which when repeated over and over again produces the complete space lattice. It represents the shape of entire crystal. The parameters which characterizes a unit cell are as follows:
1 Relative lengths (distance) of the edges along the three axis (a, b, c). These edges may or may not be equal.
2 Angle between the edges (α, β, γ).The angle α is between the edges b & c, angle β is between the edges c & a, and angle γ is between the edges a & b.
Popular Questions of Class 12 Chemistry
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Give simple chemical tests to distinguish between the following pairs of compounds.
(i) Propanal and Propanone
(ii) Acetophenone and Benzophenone
(iii) Phenol and Benzoic acid
(iv) Benzoic acid and Ethyl benzoate
(v) Pentan-2-one and Pentan-3-one
(vi) Benzaldehyde and Acetophenone
(vii) Ethanal and Propanal
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A 5% solution (by mass) of cane sugar in water has freezing point of 271 K. Calculate the freezing point of 5% glucose in water if freezing point of pure water is 273.15 K.
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How the following conversions can be carried out?
(i) Propene to propan-1-ol
(ii) Ethanol to but-1-yne
(iii) 1-Bromopropane to 2-bromopropane
(iv) Toluene to benzyl alcohol
(v) Benzene to 4-bromonitrobenzene
(vi) Benzyl alcohol to 2-phenylethanoic acid
(vii) Ethanol to propanenitrile
(viii) Aniline to chlorobenzene
(ix) 2-Chlorobutane to 3, 4-dimethylhexane
(x) 2-Methyl-1-propene to 2-chloro-2-methylpropane
(xi) Ethyl chloride to propanoic acid
(xii) But-1-ene to n-butyliodide
(xiii) 2-Chloropropane to 1-propanol
(xiv) Isopropyl alcohol to iodoform
(xv) Chlorobenzene to p-nitrophenol
(xvi) 2-Bromopropane to 1-bromopropane
(xvii) Chloroethane to butane
(xviii) Benzene to diphenyl
(xix) tert-Butyl bromide to isobutyl bromide
(xx) Aniline to phenylisocyanide
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A solution of glucose in water is labelled as 10% w/w, what would be the molality and mole fraction of each component in the solution? If the density of solution is 1.2 g mL-1, then what shall be the molarity of the solution?
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Henry's law constant for CO2 in water is 1.67 x 108Pa at 298 K. Calculate the quantity of CO2in 500 mL of soda water when packed under 2.5 atm CO2 pressure at 298 K.
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Calculate the mass of a non-volatile solute (molar mass 40 g mol-1) which should be dissolved in 114 g octane to reduce its vapour pressure to 80%.
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The vapour pressure of pure liquids A and B are 450 and 700 mm Hg respectively, at 350 K. Find out the composition of the liquid mixture if total vapour pressure is 600 mm Hg. Also find the composition of the vapour phase.
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Calculate the mole fraction of benzene in solution containing 30% by mass in carbon tetrachloride.
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Vapour pressure of pure acetone and chloroform at 328 K are 741.8 mm Hg and 632.8 mm Hg respectively. Assuming that they form ideal solution over the entire range of composition, plot ptotal' pchloroform' and pacetoneas a function of xacetone. The experimental data observed for different compositions of mixture is.
100 ×xacetone
0 11.8 23.4 36.0 50.8 58.2 64.5 72.1 pacetone /mm Hg
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Arrange the following in the order of property indicated for each set:
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(ii) medicinal chemistry
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Name the following compounds according to IUPAC system.
(i)
(ii)
(iii)
(iv)
(v)
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Why is the ester hydrolysis slow in the beginning and becomes faster after sometime?
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Nice explanation
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