Removal of H2O from atmospheric air using anhydrous CaCl2 is an example of which change- physical or chemical?
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Removal of H2O from atmospheric air using anhydrous CaCl2 is an example of which change- physical or chemical?
Physical change as CaCl2 is a hygroscopic substance which absorbs H2O without actually reacting with it.
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What will be the pO2 and pCO2 in the atmospheric air compared to those in the alveolar air?
(ii) pO2 higher, pCO2 lesser The partial pressure of oxygen in atmospheric air is higher than that of oxygen in alveolar air. In atmospheric air, pO2 is about 159 mm Hg....
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Write down the names of compounds represented by the following formula: (i) Al2(SO4)3 (ii) CaCl2 (iii) K2SO4 (iv) KNO3 (v) CaCO3
(i) Al2(SO4)3→ Aluminium sulphate (ii) CaCl2→ Calcium chloride (iii) K2SO4→ Potassium sulphate (iv) CaCO3→ Calcium carbonate
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Rusting of an article made up of iron is called (a) corrosion and it is a physical as well as chemical change
(c) corrosion and it is a chemical change
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On heating calcium carbonate gets converted into calcium oxide and carbon dioxide. (a) Is this a physical or a chemical change?
(a) Chemical change (b) Acidic and basic solutions can be prepared by dissolving the products of the above process in water CaO+H2O →Ca(OH)2 (basic solution) CO2 + H2O→H2 CO3 (acidic solution)
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Classify each of the following, as a physical or a chemical change. Give reasons. (a) Drying of a shirt in the sun.
Hint—Physical changes —(a), (b), (e) Chemical changes— (c), (d)
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Describe the role of CaCl2 in preparation of competent cells?
CaCl2is known to increase the efficiency of DNA uptake to produce transformed bacterial cells. The divalent Ca+2 ions supposedly create transient pores on the bacterial cell wall by which the...
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Ti(H2O)6]3+ is coloured while [Sc(H2O)6]3+ is colourless. Why ?
[Ti(H2O)6]3+ : In this core Ti+3 has one unpaired e- while Sc+3 does not has any unpaired electron.
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Ti(H2O)6]3+ is coloured while [Sc(H2O)6]3+ is colourless. Why ?
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Write the chemical formula of hydrated copper sulphate and anhydrous copper sulphate
(i) Hydrated copper sulphate – CuSO4.5H2O Anhydrous copper sulphate – CuSO4 Solutions Activity : (a) Heat a few crystals of copper sulphate in a dry boiling tube. (b) Add 2 – 3 drops of water...
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