Railway Board offers opulent and revered job posts to its aspirants. And it is not every year that we get the notification from Railway offering a good number of vacant seats to the multitude aspirants. But the current year 2018 brought a pleasant surprise with almost 1,20,000 seats to be filled by the valid candidates. Opportunity is here but you have to welcome it with a provident strategy.
Q1. Table salt gets moist during rainy season because
बरसात के मौसम में टेबल साल्ट नम क्यों हो जाता है?
(a) sodium chloride is hygroscopic / सोडियम क्लोराइड हाइग्रस्कापिक है.
(b) sodium chloride is deliquescent / सोडियम क्लोराइड देलिक़ुएस्केन्त है.
(c) sodium chloride contains some quantity of sodium iodide /सोडियम क्लोराइड में कुछ मात्रा सोडियम आयोडाइड की होती है.
(d) sodium chloride contains hygroscopic impurities like magnesium chloride / सोडियम क्लोराइड में मैग्नीशियम क्लोराइड जैसे हाइग्रोस्कोपिक अशुद्धताएं होती हैं
Sol. Table salt is refined salt, which contains about 97 to 99 percent sodium chloride. It usually contains substances that make it free-flowing (anticaking agents) such as sodium aluminosilicate or magnesium chloride. Because of Hygroscopic nature of salt it become wet in rainy season as the salt absorbs moisture from environment.
Q2. Which of the following is used as a lubricant in heavy machines?
भारी मशीनों में स्नेहक के रूप में निम्नलिखित में से कौन सा उपयोग किया जाता है?
(a) Bauxite / बॉक्साइट
(b) Sulphur / सल्फर
(c) Phosphorus / फास्फोरस
(d) Graphite / ग्रैफाइट
Sol. Graphite is used as a lubricant in heavy machines. It is made of carbon atoms arranged in sheets of hexagonal units-looks a lot like chicken-wire. Another sheet forms on top of this and so on. There is no proper connection (in ideal graphite) between the sheets, so they are able to slide freely over each other without breaking any bonds.
Q3. The anode in a dry cell consists of
शुष्क सेल का एनोड किस से निहित होता है?
(a) Copper / तांबा
(b) Zinc / जस्ता
(c) Cadmium / कैडमियम
(d) Graphite / ग्रैफाइट
Sol. A “dry-cell” battery is essentially comprised of a metal electrode or graphite rod (elemental carbon) surrounded by a moist electrolyte paste enclosed in a metal cylinder. The cathode is composed of a form of elemental carbon called graphite, which serves as a solid support for the reduction half-reaction. A thin zinc cylinder serves as the anode and it undergoes oxidation.
Q4. Which of the following is used to iodise common salt?
निम्नलिखित में से क्या आयोडीनयुक्त साधारण नमक की तरह उपयोग किया जाता है?
(a) Potassium iodide / पोटैशियम आयोडाइड
(b) Iodine / आयोडीन
(c) Potassium iodate / पोटेशियम आयोडेट
(d) Sodium iodide / सोडियम आयोडाइड
Sol. Iodized salt (also spelled iodised salt) is table salt mixed with a minute amount of various salts of the element iodine. Table salt with iodide salt slowly loses its iodine evaporation. Edible salt can be iodised by spraying it with a potassium iodate solution. 60 ml of potassium iodate.
Q5. Milk is a colloidal system in which:
दूध एक कोलाइडियल प्रणाली है जिसमें की :
(a) Water is dispersed in fat / वसा में पानी परिक्षेपित होता है
(b) Fat is dispersed in water / पानी में वसा परिक्षेपित होता है
(c) Fat and water dispersed / वसा और पानी परिक्षेपित होता है
(d) Fat is dissolved / वसा विघटित होता है
Sol. A colloid is a substance microscopically dispersed evenly throughout another substance. A colloidal system consists of two separate phases: a dispersed phase (or internal phase) and a continuous phase (or dispersion medium) in which the colloid is dispersed. A colloidal system may be solid, liquid, or gas. Milk is an emulsified colloid of liquid butterfat globules dispersed within a water-based solutions.
Q6. The enzyme that converts glucose to ethyl alcohol is:
एंजाइम जो ग्लूकोज को एथिल अल्कोहल में परिवर्तित करता है वह कौन सा है?
(a) Invertase / इंवरटेस
(b) Maltase /माल्टेज़
(c) Zymase /जाईमेस
(d) Diastase /डायस्टेस
Sol. The fermentation of sugar into ethanol is one of the earliest biotechnologies employed by humanity. Fermentation of fermentable sugars by suitable yeast produces ethanol (ethyl alcohol). Yeast is a single celled fungs containing a number of enzymes useful during fermentation. Brewers yeast and wine yeast, for example, contain zymase, an enzyme that can convert glucose to ethanol.
निम्नलिखित में से कौन सी ईंधन सामग्री स्वाभाविक रूप से घटित हुई?
(a) U235
(b) Pu239
(c) Pu241
(d) U-233
Sol. Uranium-235 is an isotope of uranium making up about 0.72% of natural uranium.
भारी पानी क्या है?
(a) Oxygen+Heavy Hydrogen / ऑक्सीजन + भारी हाइड्रोजन
(b) Hydrogen+Oxygen / हाइड्रोजन + ऑक्सीजन
(c) Hydrogen+New Oxygen / हाइड्रोजन + नया ऑक्सीजन
(d) Heavy Hydrogen+Heavy Oxygen / भारी हाइड्रोजन + भारी ऑक्सीजन
Sol. Oxygen+Heavy Hydrogen or deuterium
भारी पानी वह पानी है –
(a) The temperature of which is kept constant at 4°C / जिसका तापमान 4 डिग्री सेल्सियस पर स्थिर रहता है
(b) In which insoluble salts of Calcium and Potassium are present / कैल्शियम और पोटेशियम के अघुलनशील लवण मौजूद हैं
(c) In which isotopes takes place of Hydrogen / जिसमें आइसोटोप हाइड्रोजन की जगह ले लेते है
(d) In which isotopes takes place of Oxygen / जिसमें आइसोटोप ऑक्सीजन की जगह ले लेते है
Sol.Heavy water is that water In which isotopes takes place of Hydrogen.
निम्नलिखित में से किसने भारी पानी की खोज की?
(a) Heinrich Hertz / हेनरिक हर्ट्ज
(b) H.C. Urey / एच.सी. उरे
(c) G. Mendel / जी. मेंडेल
(d) Joseph Priestly / जोसेफ़ प्रिएस्त्ल्य
Sol. Harold Clayton Urey, an American Chemist discovered heavy water in 1931. He was awarded Nobel Prize in Chemistry in 1934 for this discovery.
निम्नलिखित कथनों पर विचार करें:
Hard water is not suitable for
कठोर जल किस के लिए उपयुक्त नहीं है
1. Drinking / पीने के लिए
2. Washing clothes with soap / साबुन से कपडें धोने के लिए
3. Use in boilers / बॉयलर में प्रयोग के लिए
4. Irrigating crops / फसल सींचने के लिए
Which of these statements are correct?
इनमें से कौन सा कथन सही 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
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.
प्रशीतन खाद्य संरक्षण में कैसे मदद करता है?
(a) Killing the germs / रोगाणुओं को मारना
(b) Reducing the rate of biochemical reactions / जैव रासायनिक प्रतिक्रियाओं की दर को कम करना
(c) Destroying enzyme action / एंजाइम क्रिया को नष्ट करना
(d) Sealing the food with a layer of ice / बर्फ की परत से, खाने को सील करना
Sol. Refrigeration preserves foods by slowing down the growth and reproduction of micro-organisms or we can say that by refrigeration we can reduce the rate of biochemical reactions.
चारकोल जो की कच्ची चीनी का रंग बिगाड़ने में इस्तेमाल की जाती है वह क्या है?
(a) Wood charcoal / लकड़ी चारकोल
(b) Sugar charcoal / चीनी चारकोल
(c) Animal charcoal / पशु चारकोल
(d) Coconut charcoal / नारियल चारकोल
Sol. Animal charcoal also, known as Bone charcoal is primarily used for filtration and decolorization. Bone charcoal is often used in sugar refining as a decolorizing and de-ashing agent.
शहद का मुख्य घटक क्या है?
(a) Glucose / ग्लूकोज़
(b) Sucrose / सुक्रोज
(c) Maltose / माल्टोस
(d) Fructose / फ्रुक्टोज
Sol. The main components of honey are fructose – 38.2%, glucose -31.3%, sucrose – 1.3%, maltose – 7.1% and water -17.2% Fructose or fruit sugar is a simple ketonic monosaccharide found in many plants.
एस्पिरिन किस से प्राप्त किया जाता है?
(a) Petroleum / पेट्रोलियम
(b) Earth / पृथ्वी
(c) A tree / पेड़
(d) Chemical reaction of acids / एसिड की रासायनिक प्रतिक्रिया
Sol. Aspirin is a salicylate. It works by reducing substances in the body that cause pain, fever and inflammation. It is sometimes used to treat or prevent heart attacks, strokes and chest pain. It is obtained from latex tree.