During sulphonation of benzene H2SO4 generates the electrophile ---------?
During sulphonation of benzene H2SO4 generates the electrophile ---------?
SO2 | |
SO3 | |
HSO4- | |
H+ |
پاک اسٹڈی لائبریری اپنی خدمات کو بہتر کرنے کے لئے نئے سوفٹ وئیر انسٹال کررہی ہے ۔ اس لئے آئندہ کچھ دن آپ کو کچھ صفحات تک رسائی میں مشکلات کا سامنا ہوسکتا ہے ۔ جس کے لئے ہم معذرت خواہ ہیں۔
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During sulphonation of benzene H2SO4 generates the electrophile ---------?
SO2 | |
SO3 | |
HSO4- | |
H+ |
Dry distillation of calcium acetate results in the formation of---------?
acetaldehyde | |
methane | |
formaldehyde | |
acetone |
Downs cell is used to prepare---------?
Sodium hydroxide | |
Sodium metal | |
Sodium bicarbonate | |
Sodium carbonate |
Distance at which attractive forces of hydrogen overcome repulsive forces is ----- ?
75.2pm | |
75.5pm | |
75.4pm | |
75.3pm |
Direct conversion of solids into vapours is called ----------?
vaporization | |
crystallization | |
sublimation | |
Solvent extraction |
Different components of a mixture have different Rf values due to--------?
Distributive law | |
Their different distribution coefficients in the solvent | |
Combination of solvents used | |
Polar solvent used |
Diameter of an atom is in the order of--------?
0.2mm | |
0.2nm | |
0.2m | |
0.2pm |
Deuterium reacts with oxygen to form--------?
Hard water | |
Soft water | |
Heavy water | |
Water gas |
Density of H2SO4 in lead accumulator is---------?
1.20g/cm3 | |
1.3g/cm3 | |
1.15g/cm3 | |
1.25g/cm3 |
Dempsters mass spectrometer has number of zones / parts---------?
5 | |
2 | |
4 | |
3 |
Dehalogenation of ethyl tetrahalide will give----------?
ethene | |
all of the above are possible | |
ethyl halide | |
ethyne |
Decrease in oxidation number is called---------?
reduction | |
oxidation | |
all of above represent same entity | |
oxidation- |
DAP (Diammonium hydrogen phosphate) contains ------- plant nutrients?
75% | |
70% | |
60% | |
65% |
Crystals of Na2CO3. 10H2O when exposed to air---------?
Remains unchanged | |
Gain water and become liquid | |
Lose water and remain solid | |
Gain water and remain solid |
Crystallization does not involve--------?
heating | |
cooling | |
sublimation | |
vaporization |
Crystallites are present in---------?
liquid crystals | |
crystalline solids | |
all of the above | |
amorphous solids |
Crystalline solids can be identified easily from their ----------?
Sharp melting point | |
Colour | |
Definite geometry | |
Transition temperature |
Critical temperature for different gases is different and depends upon-------?
Shape of molecule | |
All of the above | |
Intermolecular attractions | |
Size of molecule |
Coordination number of the transition element in [Pt Cl NO2 (NH3)4]2- is----------?
2 | |
8 | |
6 | |
4 |
Conversion of reactant into product in unit time is called--------?
rate of forward reaction | |
rate co-efficient | |
rate of backward reaction | |
rate constant |
Consider the following redox reaction. Zn+dil HNO3? Zn (NO3)2 + N2O + H2O The coefficient number of HNO3 in the equation is---------?
4 | |
8 | |
10 | |
6 |
Consider the following reaction- 3Cl2 + 6NaOH ? NaClO3 + 5NaCl + 3H2O This reaction is--------?
Double displacement reaction | |
Disproportionation reaction | |
Displacement reaction | |
Reduction reaction |
Consider the following reaction- 2KCIO3 + H2C2O4 + H2SO4 ? K2SO4 + 2H2O + 2CO2 + Oxide Which oxide of chlorine is produced in the above reaction ?
Cl2O6 | |
Cl2O7 | |
ClO2 | |
Cl2O |
Conjugated base of a weak acid is---------?
moderately weak | |
strong | |
weak | |
unstable |
Concept of Triads was introduced by--------?
Al-Razi | |
Mendeleev | |
Dobereiner | |
Newland |