Silver crystallises in fcc lattice. If edge length of the cell is 4.07 x 10-8cm and density is 10.5 g cm-3, calculate the atomic mass of silver.
From the equation, density = ZxM/a3 x N0, we get
M = ρ x a3 x N0/Z …………………………………1
Placing the values in equation 1,
WE GET M= 10.5 x (4.07 x10-8)3 x 6.022 x 1023/4
= 106.6 gmol-1
= Therefore, atomic mass of silver = 106.6 gmol-1
If NaCl is doped with 10-3mol % of SrCl2, what is the concentration of cation vacancies?
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An element with molar mass 2.7 x 10-2kg mol-1 forms a cubic unit cell with edge length 405 pm. If its density is 2.7 x 103 kg m-3, what is the nature of the cubic unit cell?
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Aluminium crystallises in a cubic close-packed structure. Its metallic radius is 125 pm.
(i) What is the length of the side of the unit cell?
(ii) How many unit cells are there in 1.00 cm3of aluminium?
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Distinguish between
(i)Hexagonal and monoclinic unit cells
(ii) Face-centred and end-centred unit cells.
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Write the formulas for the following coordination compounds:
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(ii) Potassium tetracyanonickelate(II)
(iii) Tris(ethane-1,2-diamine) chromium(III) chloride
(iv) Amminebromidochloridonitrito-N-platinate(II)
(v) Dichloridobis(ethane-1,2-diamine)platinum(IV) nitrate
(vi) Iron(III) hexacyanoferrate(II)
(i) Write structures of different isomeric amines corresponding to the molecular formula, C4H11N
(ii) Write IUPAC names of all the isomers.
(iii) What type of isomerism is exhibited by different pairs of amines?
Write any two characteristics of Chemisorption.
Write the structures of the following compounds.
(i) α-Methoxypropionaldehyde
(ii) 3-Hydroxybutanal
(iii) 2-Hydroxycyclopentane carbaldehyde
(iv) 4-Oxopentanal
(v) Di-sec-butyl ketone
(vi) 4-Fluoroacetophenone
Which of the ores mentioned in Table 6.1 can be concentrated by magnetic separation method?
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Silver atom has completely filled d orbitals (4d10) in its ground state. How can you say that it is a transition element?
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Write structures of the following compounds:
(i) 2-Chloro-3-methylpentane
(ii) 1-Chloro-4-ethylcyclohexane
(iii) 4-tert. Butyl-3-iodoheptane
(iv) 1,4-Dibromobut-2-ene
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(i) electronic configurations,
(ii) oxidation states,
(iii) ionisation enthalpies, and
(iv) atomic sizes.
The conductivity of 0.20 M solution of KCl at 298 K is 0.0248 Scm-1. Calculate its molar conductivity.
Give the structures and IUPAC names of monohydric phenols of molecular formula, C7H8O.