Chemistry GK Questions Quiz-1

Chemistry GK Questions Quiz-1

Chemistry Multiple Choice Questions (MCQs) Quiz for State and UPSC Civil Services Examinations. Objective Questions on Chemistry for competitive examinations.

    1. Baryllium Sulphate is less soluble in water due to

    (1) High inflammable energy
    (2) Low Energy of dissociation
    (3) Low inflammable energy
    (4) Lonic band
    Answer:
    1. (1) Baryllium sulfate (BeSO4) is a white crystalline solid. It was first isolated in 1815 by Jons Jakob Berzelius. Beryllium sulfate may be prepared by treating an aqueous solution of any beryllium salt with sulfuric acid, followed by evaporation of the solution and crystallization. The hydrated product may be converted to anhydrous salt by heating at 400°C. Baryllium Sulphate is less soluble in water due to High inflammable energy.

    2. What is the name of that system, which uses radioactivity to decide the period of materials of-pre-historic period ?

    (1) Radium dating
    (2) Uranium dating
    (3) Carbon dating
    (4) Deuterium dating
    Answer:
    2. (3) Radiocarbon dating (usually referred to as simply carbon dating) is a radiometric dating method that uses the naturally occurring radioisotope carbon-14 (14C) to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years.


    3. Cement is made hard with

    (1) dehydration
    (2) hydration and dissociation of water
    (3) Dissociation of water
    (4) Polymerisation
    Answer:
    3. (2) Cements (e.g., Portland cement) harden because of hydration, chemical reactions that occur
    independently of the mixture’s water content; they can harden even underwater or when constantly
    exposed to wet weather. The chemical reaction that results when the anhydrous cement powder is mixed with water produces hydrates that are not water soluble.

    4. What happens when a chemical bond is formed ?

    (1) energy is always absorbed
    (2) energy in always released
    (3) more energy is released than is absorbed
    (4) energy is neither released nor absorbed
    Answer:
    4. (1) If a bond is broken, energy is released; and if a bond is formed, energy must have been absorbed.
    As these occur, a change in the chemical energy of the system also occurs. Within each bond of a molecule is an experimentally determined amount of energy that upon the breaking of that bond is released into the chemical system. The energy within these bonds are ‘stored’ and can be easily thought of as potential energy. Upon the breaking of these bonds the energy is released thereby creating usable energy.


    5. Which among the following is a carbohydrate ?

    (1) Nylon
    (2) Cane-sugar
    (3) Turpentine
    (4) Hydrogen peroxide
    Answer:
    5. (2) Cane-sugar is carbohydrate and as this name implies, is composed of carbon, hydrogen and oxygen. it is a source of extracting sugar. There are various types of sugar derived from different sources. Simple sugars are called monosaccharides and include glucose, fructose and galactose. The table or granulated sugar most customarily used as food is sucrose, a disaccharide. Other disaccharides include maltose and lactose.

    6. In which of the following states maximum iron ore is found ?

    (1) FeCO3 
    (2) Fe2O3
    (3) Fe3O4 
    (4) FeS2
    Answer:
    6. (2) Iron ores are rocks and minerals from which metallic iron can be economically extracted. The iron itself is usually found in the form of magnetite (Fe3O4), hematite (Fe2O3), goethite (FeO(OH), limonite (FeO(OH).n(H2O)) or siderite (FeCO3). Hematite, also spelled as haematite, is the mineral form of iron(III) oxide (Fe2O3), one of several iron oxides. It is mined as the main ore of iron. Huge deposits of hematite are found in banded iron formations. Gray hematite is typically found in places where there has been standing water or mineral hot springs, such as those in Yellowstone National Park in the United States.


    7. “All the four quantum numbers of two electrons in an atom are not the same.” It is the law of —

    (1) Hund’s
    (2) Exclusion Principle of Pauli
    (3) Uncertainty Principle of Hiesenberg
    (4) Avogadro’s Law
    Answer:
    7. (2) The Pauli exclusion principle is the quantum mechanical principle that no two identical fermions
    (particles with half-integer spin) may occupy the same quantum state simultaneously. A more rigorous
    statement is that the total wave function for two identical fermions is anti-symmetric with respect to
    exchange of the particles. For example, no two electrons in a single atom can have the same four
    quantum numbers; if n, l, and ml are the same, ms must be different such that the electrons have
    opposite spins.


    8. Commercial nitric acid is coloured because it contains dissolved :

    (1) Oxygen
    (2) Nitrous oxide
    (3) Nitrogen dioxide
    (4) Coloured impurities
    Answer:
    8. (3) Commercial nitric acid has a brown colour due to dissolved NO2. The procedure of bubbling dry air through warm commercial nitric acid, is to drive away the dissolved nitrogen dioxide so that the acid becomes colourless.


    9. Fertiliser having high nitrogen content is :

    (1) Urea
    (2) Ammonium sulphate
    (3) Ammonium nitrate
    (4) Calcium citrate
    Answer:
    9. (3) A growth fertilizer will have a high N content and relatively low P and K content. Ammonium nitrate is the highest Nitrogen fertilizer you can buy, and it is potent stuff. It is usually rated as 33-0-0 or 34-0-0. The bag contains 33% or 34% Nitrogen and the other 66% or 67% is inert material. Other formulations of growth fertilizers will contain 5, 6 or even 7 times more Nitrogen than anything else.


    10. Where does the oxygen that keeps us alive come from?

    (1) Carbon dioxide
    (2) Carbonates absorbed from soil
    (3) Oxides of minerals
    (4) Water
    Answer:
    10. (4) Since water and carbon dioxide are both compounds which contain oxygen, it is possible to obtain oxygen from either. The oxygen produced from photosynthesis is not released into the air. It is not until cellular respiration that oxygen is released. The oxygen comes from water. The water molecules are split at the “beginning” of photosynthesis for the electrons. These electrons eventually make their way to the electron transport chain, where oxygen is the final electron accept, and then released into the air. Scientists agree that there’s oxygen from ocean plants in every breath we take. Most of this oxygen comes from tiny ocean plants – called phytoplankton – that live near the water’s surface and drift with the currents. Like all plants, they photosynthesize – that is, they use sunlight and carbon dioxide to make food. A byproduct of photosynthesis is oxygen.

    11. The gas used for artificial fruit ripening of green fruit is —

    (1) Ethylene 
    (2) Acetylene
    (3) Ethane 
    (4) Methane
    Answer:
    11. (1) Ethylene can promote ripening in tomatoes, bananas, citrus, pineapples, dates, persimmons,
    pears, apples, melons, mangos, avocados, papayas and jujubes - a clear indication that the action of
    ethylene is general and widespread amongst a number of fruits. It is clear that ethylene is a ripening hormone - a chemical substance produced by fruits with the specific biological phenomenon of accelerating the normal process of fruit maturation and senescence.


    12. The three elements most needed in common fertilisers are :

    (1) Sulphur, Phosphorous and Sodium
    (2) Nitrogen, Potassium and Phosphorous
    (3) Phosphorous, Sodium and Nitrogen
    (4) Calcium, Phosphorous and Potassium
    Answer:
    12. (2) Fertilizer (or fertiliser) is any organic or inorganic material of natural or synthetic origin (other than liming materials) that is added to a soil to supply one or more plant nutrients essential to the growth of plants. The three elements most needed in common fertilisers are Nitrogen. Potassium and Phosphorous.


    13. Which one of the following metals pollutes the air of a city having large number of automobiles?

    (1) Cadmium 
    (2) Chromium
    (3) Lead 
    (4) Copper
    Answer:
    13. (3) The history of car pollution has been one of air and water contamination followed by regulated
    improvement. Cars and trucks cause a lot of air the pollution in the world today, and contribute a lot to
    the most common and dangerous air pollutants. About 2.3 million tons of lead in lead acid (PbA) batteries is on the road now. Over 1 million tons of lead is used in making new batteries each year. In the past, motor vehicles were the biggest source of lead. But since leaded gasoline has been phased out, lead emissions have decreased by about 98 percent. Today, metal processing is the biggest source of atmospheric lead. The highest air concentrations are found in the vicinity of ferrous and nonferrous smelters and battery manufacturers.

    14. What is the chemical name for ‘baking soda’?

    (1) Sodium carbonate
    (2) Sodium bicarbonate
    (3) Sodium nitrite
    (4) Sodium nitrate
    Answer:
    14. (2) Sodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula
    NaHCO3. Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda (sodium carbonate). Since it has long
    been known and is widely used, the salt has many related names such as baking soda, bread soda,
    cooking soda, and bicarbonate of soda.


    15. An atomic pile is used for

    (1) producing X-rays
    (2) conducting nuclear fission
    (3) coducting thermonuclear fusion
    (4) accelerating atoms
    Answer:
    15. (2) An atomic pile is a nuclear reactor that uses controlled nuclear fission to generate energy. The
    most common reactor consists of a large assembly of graphite (an allotropic form of carbon) blocks having rods of uranium metal (fuel).


    16. Which of the following gases is present under pressure in soft drinks?

    (1) Oxygen 
    (2) Nitrogen
    (3) Carbon dioxide
    (4) Nitrous oxide
    Answer:
    16. (3) Carbon dioxide is present under pressure in soft drinks. Carbon dioxide adds that special sparkle and bite to the beverage and also acts as a mild preservative. Carbon dioxide is an uniquely suitable
    gas for soft drinks because it is inert, non-toxic, and relatively inexpensive and easy to liquefy.

    17. The substance which does not expand on going from liquid state to solid state is

    (1) Water 
    (2) Cast-iron
    (3) Aluminium
    (4) Type metal
    Answer:
    17. (4) In printing, type metal (sometimes called hot metal) refers to the metal alloys used in traditional type founding and hot metal typesetting. Lead is the main constituent of these alloys. Antimony and tin are added to make the character produced durable and tough while reducing the difference between the coefficients of expansion of the matrix and the alloy. Pure metal melts and solidifies in a simple manner at a specific temperature. This is not the case with alloys.


    18. The radio-active element used in heart pacemakers is

    (1) Uranium 
    (2) Deuterium
    (3) Plutonium 
    (4) Radium
    Answer:
    18. (1) The actinides (or actinoids) are the chemical elements with atomic numbers between 90 and 109
    inclusively. They occur between Groups 3 and 4 in Period 7 of the periodic table. All elements in this
    family are radioactive. Five actinides namely: thorium, protoactinium, uranium, neptunium, and plutonium have been found in nature. Plutonium is used in the manufacture of nuclear weapons and as the power source in nuclear power plants. On a smaller scale, it is also used as a power source in smaller devices such as the heart pacemaker.


    19. The element which is commonly used in nuclear for producing electricity by nuclear fission is

    (1) Radium 
    (2) Plutonium
    (3) Uranium 
    (4) Deuterium
    Answer:
    19. (3) Uranium is used to produce a chemical and nuclear reaction which makes a lot of heat. This heat is used to turn water into steam, which turns turbines...turbines generate electricity.


    20. Table salt gets moist during rainy season because

    (1) sodium chloride is hygroscopic
    (2) sodium chloride is deliquescent
    (3) sodium chloride contains some quantity of sodium iodide
    (4) sodium chloride contains hygroscopic impurities like magnesium chloride
    Answer:
    20. (4) 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 carbonate. Because of Hygroscopic nature of salt it become wet in rainy season as the salt absorbs moisture from environment.


    यह भी देखे :




















    Post a Comment

    0 Comments