Mole Concept (Assignment) - Shailendra Kumar Chemistry
Mole Concept (Assignment) - Shailendra Kumar Chemistry
Mole Concept (Assignment) - Shailendra Kumar Chemistry
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PHYSICAL CHEMISTRY By: <strong>Shailendra</strong> <strong>Kumar</strong><br />
45) Chemical absorbers can be used to remove exhaled CO of space travelers in short space<br />
2<br />
flights. Li O is one of the most efficient in terms of absorbing capicity per unit weight. If the<br />
2<br />
reaction is Li O + CO Li CO , What is the absorption efficiency of pure Li O in L CO 2 2 2 3 2 2<br />
(STP) per kg ?<br />
Ans : 750 L<br />
46) Calcium carbide, CaC reacts with water to produce acetylene, C H and calcium hydroxide<br />
2 2 2<br />
Ca (OH) . Calculate the volume of C H (g) at 25ºC and 0.950 atm produced from the reaction<br />
2 2 2<br />
of 128 gm CaC with 45 gm water.<br />
2<br />
CaC + 2H O 2 2 Ca (OH) + C H 2 2 2<br />
Ans : 32.2 Litre<br />
47) When 0.75 mole solid “A ” and 2 mole gaseous O are heated in a sealed vessel (Bomb)<br />
4 2<br />
completely using up the reactants and producing only one compound, it is found that when the<br />
temperature is reduced to the initial temperature, the contents of the vessel exhibit a pressure<br />
equal to half the original pressure. What is molecular formula of the product.<br />
Ans : A O 3 4<br />
48) Calculate orally,<br />
(i) How many moles of CaCO shall be produced from 5 moles of Ca atom ?<br />
3<br />
(ii) How many moles of BaSO shall be formed from 5 moles of BaCl ?<br />
4 2<br />
(iii) How many moles of Na O shall be produced from 5 moles of Na atom ?<br />
2<br />
Ans : (i) 5, (ii) 5 and (iii) 2.5<br />
49) What weight of oxygen will react with 40 g of Ca ?<br />
Ans : 16 g<br />
50) Calculate the volume of acetylene at NTP produced by 100 g of CaC with water.<br />
2<br />
Ans : 35 litre<br />
51) 4.90 g of KClO , on heating, shows a weight loss of 0.384 g. What percent of the original<br />
3<br />
KClO has decomposed ?<br />
3<br />
Ans : 20%<br />
52) Calculate the weight of V O produced from 2 g of VO and 5.75 g of Fe O .<br />
2 5 2 3<br />
VO + Fe O FeO + V O 2 3 2 5<br />
Ans : 2.18 g<br />
53) 1 g of dry green algae absorbs 4.7 × 10 –3 mole of CO per hour by photosynthesis. If the fixed<br />
2<br />
carbon atoms were all stored after photosynthesis as starch, (C H O ) , how long would it<br />
6 10 5 n<br />
take for the algae to double their own weight assuming photosynthesis takes place at a constant<br />
rate ?<br />
Ans : 7.88 hour<br />
54) The mixture of MgCO and CaCO , when heated decompose to give CO and MgO. What is<br />
3 3 2<br />
the percentage of MgCO in the mixture which decreases in weight by 50% when heated for a<br />
3<br />
long time to expel all the CO ? 2<br />
Ans : 95.5%<br />
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Page No.: 6
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