Chemistry Questions for Railway 2018: 11 May

Chemistry Questions for Railway 2018: 11 May

Chemistry Questions for Railway 2018: 11 May

Q1. An element X has four electrons in its outermost orbit. What will be the formula of its compounds with Hydrogen? 
एक तत्व X में इसकी बाहरी कक्षा में चार इलेक्ट्रॉन हैं. हाइड्रोजन के साथ इसके यौगिकों का सूत्र क्या होगा?
(a) X_4 H
(b) X_4 H_4
(c) XH_3
(d) XH_4

Show Answer
Ans.(d)
Sol. The compounds of element X which has four electrons in its outermost orbit will be XH4.

Q2. According to weight, the percentage of Hydrogen in water (H_2 O), is- 
वजन के अनुसार, पानी में हाइड्रोजन का प्रतिशत (H2O), है? 
(a) 44.45%
(b) 5.55%
(c) 88.89%
(d) 11.11%

Show Answer
Ans.(d)
Sol. Percentage of composition is the percent by mass of each element present in a compound.
In Water, H_2 O = 2 + 16 = 18 g/mol
Molecular weight of water 18.0152 grams.
No. of Hydrogen atoms present in Water = 2
∴ Percentage of Hydrogen in water
=2/18×100=11.11%

Q3. Burning of Hydrogen produces-
 हाइड्रोजन के जलने से क्या उत्पन्न होता है – 
(a) Oxygen  / ऑक्सीजन
(b) Ash  / राख
(c) Soil  / मृदा
(d) Water  / पानी

Show Answer
Ans.(d)
Sol. Hydrogen gas is highly flammable and burns in air at a very wide range of concentrations between 4% to 75% by volume. Hydrogen gas cannot burn in absence of air. But by burning with Oxygen it produces water.

Q4. Which one of the following fuels causes minimum air pollution? 
 निम्नलिखित से कौन सा ईंधन न्यूनतम वायु प्रदूषण का कारण बनता है?
(a) Kerosene oil  //किरोसीन तेल
(b) Hydrogen /हाइड्रोजन
(c) Coal /  कोयला
(d) Diesel  / डीज़ल

Show Answer
Ans.(b)
Sol. Hydrogen is the purest combustion fuel. Water is generated from burning of Hydrogen. While coal, kerosene oil and diesel are known as fossil fuel or carbonic fuel which generates Carbon dioxide and many other harmful gases when it burns.

Q5. Hydrogen can be obtained from water by ?
हाइड्रोजन पानी से प्राप्त किया जा सकता है?
(a) Reaction with metal oxide  / धातु ऑक्साइड के साथ प्रतिक्रिया
(b) Reaction with non-metal oxide  / गैर धातु ऑक्साइड के साथ प्रतिक्रिया
(c) Reaction with metals / धातुओं के साथ प्रतिक्रिया
(d) Reaction with metal Hydrides / धातु हाइड्राइड के साथ प्रतिक्रिया

Show Answer
Ans.(c)
Sol. Mg(metal) +2H2O= Mg(OH)2+H2

Q6. The chemical formula of Heavy water is? 
हैवी पानी का रासायनिक सूत्र क्या है ?
(a) H_2 O
(b) D_2 O
(c) H_2 CO_3
(d) H_2 S

Show Answer
Ans.(b)
Sol. Heavy water (D_2 O) Deuterium Oxide is used as a moderator and coolant in nuclear reactors because it slows down neutrons effectively and also has a low probability of absorption of neutrons. Deuterium is an isotope of Hydrogen which comprises both a neutron and a proton. D_2 O is a form of water which reacts with Oxygen to form Deuterium Oxide (D_2 O), also known as heavy water.

Q7. The substance used as moderator and coolant both, in nuclear reactors is: 
परमाणु रिएक्टरों में मॉडरेटर और शीतलक दोनों के रूप में उपयोग किया जाने वाला पदार्थ _______है
(a) Ordinary water  / आर्डिनरी पानी
(b) Heavy water  / हैवी पानी
(c) Liquid Ammonia  / लिक्विड अमोनिया
(d) Liquid Hydrogen  / लिक्विड हाइड्रोजन

Show Answer
Ans.(b)
Sol. Heavy water (D_2 O) Deuterium Oxide is used as a moderator and coolant in nuclear reactors because it slows down neutrons effectively and also has a low probability of absorption of neutrons. Deuterium is an isotope of Hydrogen which comprises both a neutron and a proton. D_2 O is a form of water which reacts with Oxygen to form Deuterium Oxide (D_2 O), also known as heavy water.

Q8. What is heavy water? 
हैवी पानी क्या है? 
(a) Oxygen + Heavy Hydrogen  / ऑक्सीजन + हैवी हाइड्रोजन
(b) Hydrogen + Oxygen  / हाइड्रोजन + ऑक्सीजन
(c) Hydrogen + New Oxygen /  हाइड्रोजन + न्यू ऑक्सीजन
(d) Heavy Hydrogen + Heavy Oxygen /  हैवी हाइड्रोजन + हैवी ऑक्सीजन

Show Answer
Ans.(a)
Sol. Heavy water (D_2 O) Deuterium Oxide is used as a moderator and coolant in nuclear reactors because it slows down neutrons effectively and also has a low probability of absorption of neutrons. Deuterium is an isotope of Hydrogen which comprises both a neutron and a proton. D_2 O is a form of water which reacts with Oxygen to form Deuterium Oxide (D_2 O), also known as heavy water.

Q9. The usual valence of hydrogen is: 
हाइड्रोजन की सामान्य संयुजता है:
(a) -2
(b) 0
(c) +1 or sometimes -1
(d) +2

Show Answer
Ans.(c)
Sol. Hydrogen can either gain or lose an electron to have a stable electron shell, giving it a valence of +1 or -1.

Q10. Who among the following discovered heavy water? 
इनमे से हैवी पानी किसके द्वारा खोजा गया था?
(a) Heinrich Hertz  /  हेनरिक हर्ट्ज
(b) H.C. Urey /  एच.सी. Urey
(c) G. Mendel  / जी मेंडेल
(d) Joseph Priestly / यूसुफ प्रीस्टली

Show Answer
Ans.(b)
Sol. Harold Clayton Urey, an American Chemist discovered heavy water in 1931. He was awarded Nobel Prize in Chemistry in 1934 for this discovery.

Q11. Consider the following statements: 
निम्नलिखित कथनों को ध्यानपूर्वक पढ़िए.
Hard water is not suitable 
कठोर जल उपयुक्त नहीं है:
1. Drinking / पीने के लिए 
2. Washing clothes with soap / साबुन के साथ कपड़े धोने के लिए  
3. Use in boilers / बायलर में उपयोग करने के लिए 
4. Irrigating crops / फसलों की सिंचाई के लिए 

Which of these statements are correct? 
इनमे से कौन सा कथन सत्य है ?
(a) 1 and 2 / 1 और 2
(b) 2 and 3   / 2 और 3
(c) 1, 2 and 4   / 1,2 और 4
(d) 1, 2, 3 and 4  / 1,2,3 और 4

Show Answer
Ans.(d)
Sol. Drinking water is described as “hard” due to the presence of highly dissolved minerals specifically sulphates of Calcium and Magnesium Chloride. It is very difficult to wash clothes with hard water as it requires more soap and leaves a messy scum that cannot be washed out easily. When hard water is boiled at home or in industries, it leaves deposits of Calcium and Magnesium salts. These deposits reduce the efficiency of boilers, kettles and pipes and can cause blockages and even burst of the boilers. If salt level increases in irrigation water, it becomes harder for lawns and landscape plant to take up water even though the soil is moist. Consequently, more salty water requires extra effort to irrigate.

Q12. Permanent hardness of water is due to-
 पानी की स्थायी कठोरता की वजह है:
(a) Chlorides and sulphates of Calcium and Magnesium / कैल्शियम और मैग्नेशियम के क्लोराइड और सल्फाट
(b) Calcium bicarbonate sulphates / कैल्शियम बिकारबोनेट सल्फ़ेट्स
(c) Magnesium bicarbonate  / मैग्नेशियम बाइकार्बोनेट
(d) Clorides of Silver and Potassium  / सिल्वर और पोटेशियम के क्लोराइड्स

Show Answer
Ans.(a)
Sol. Drinking water is described as “hard” due to the presence of highly dissolved minerals specifically sulphates of Calcium and Magnesium Chloride. It is very difficult to wash clothes with hard water as it requires more soap and leaves a messy scum that cannot be washed out easily. When hard water is boiled at home or in industries, it leaves deposits of Calcium and Magnesium salts. These deposits reduce the efficiency of boilers, kettles and pipes and can cause blockages and even burst of the boilers. If salt level increases in irrigation water, it becomes harder for lawns and landscape plant to take up water even though the soil is moist. Consequently, more salty water requires extra effort to irrigate.

Q13. Which is the purest form of water? 
पानी का सबसे शुद्ध रूप कौन सा है?
(a) Tap water  / नल का पानी
(b) Sea water  / सागर का पानी
(c) Rainwater  / वर्ष का पानी
(d) Distilled water / आसुत पानी
Show Answer
Ans.(c)
Sol. Rainwater gets its compositions largely by dissolving particulate materials in the atmosphere (upper troposphere) when droplets of water nucleate on atmospheric particulates and secondly by dissolving gases from the atmosphere. Its pH value is 7 whereas the water on the earth is mixed with an alkaline material that makes the water impure. 

Q14. Water is a good solvent of ionic salts because-
पानी आयनिक लवण का एक अच्छा विलायक है क्योंकि-
(a) It has a high boiling point  / इसका उच्च क्वथनांक है
(b) It has a high dipole moment / इसमें एक उच्च द्विध्रुव आघूर्ण है
(c) It has a high specific heat  / इसमें उच्च विशिष्ट आघूर्ण है
(d) It has no colour  / इसका  कोई रंग नहीं है

Show Answer
Ans.(b)
Sol. Water is a good solvent due to its polarity which can easily dissolve into polar compounds. Water dissolves ionic salts by hydrating their component ions. For example, water dissolves NaCl by hydrating and stabling the Na+ and Cl– ions.
Q15. Large quantities of drinking water is prepared from impure water by- 
अशुद्ध पानी से पीने के पानी की बड़ी मात्रा को किसके द्वारा तैयार किया जाता है -  
(a) Desalination  / डिसेलिनेशन
(b) Distillation  / आसवन
(c) Ion-exchange  / आयन विनिमय
(d) Decantation  / निस्तारण

Show Answer
Ans.(a)
Sol. Desalination is a process that removes minerals from saline water (Also refer to removal of salts and minerals). Seawater desalination has a very effective way of production of potable water for drinking and industries.
Share To:

IBTS INDIA

IBTS - (Institute for Banking Training & Educational Services) is in the Leading Institution for banking & SSC, IBPS, Center & State exams in Chandigarh.

Post A Comment:

0 comments so far,add yours