Chemistry GK Questions Quiz-42

Chemistry GK Questions Quiz-42

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

    821. In which of the following ions, the colour is not due to d-d transition ?

    (1) [Ti(H2O)6]3+ 
    (2) CoF63–
    (3) MnO–4 
    (4) [Cu(NH3)4]2+
    Answer:
    821. (3) The colour of transition-metal compounds is normally associated with d-d transitions. However, some transition metal compounds show intense colour in solution in spite of absence of d-electrons. For example, the orange colour of TiBr4, yellow colour of CrO42–, orange colour of Cr2O2–7, intense red colour of [Fe(SCN)4] and deep purple of MnO4 are not due to d—d transitions. In the case of MnO4 ion, the color is due to charge transfer and not due to d-d transitions.

    822. Adding Cl2 to benzene in the presence of AlCl3 is an example of :

    (1) Elimination reaction
    (2) Substitution reaction
    (3) None of the options
    (4) Addition reaction
    Answer:
    822. (2) The reaction between benzene and chlorine in the presence of a catalyst such as aluminium chloride gives Chlorobenzene. This reaction is an example of electrophilic substitution reaction since one of the hydrogen atoms on the ring is replaced by a chlorine atom.

    823. Which one of the following has a maximum tendency to form M3 ion ?

    (1) N 
    (2) Bi
    (3) P 
    (4) As
    Answer:
    823. (1)Thee general electronic configuration of group 15 elements (N, P, As, Sb and Bi) is ns2np3. Since Nitrogen has smallest size and greatest electronegativity in the family, it may gain three electrons and attain noble gas configuration, forming nitride N3- ions. The other members show little tendency to form tri-negative M3- ions. Their electronegativity is so low that they would generally form covalent compounds even with highly electropositive elements.

    824. Copper substances when exposed to air gains a green coating due to the formation of:

    (1) CuO
    (2) CuCO3 Cu(OH)2
    (3) CuSO4
    (4) Cu(NO3)2
    Answer:
    824. (2)When copper is exposed to air, it reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains a green coat. This green substance is basic copper carbonate (CuCO3. Cu(OH)2). The formation of this green coating on the surface of a copper object corrodes it.

    825. The chief constituent of natural gas is:

    (1) Methane 
    (2) Helium
    (3) Nitrogen 
    (4) Propane
    Answer:
    825. (1) Natural gas is a naturally occurring hydrocarbon gas mixture consisting primarily of methane (CH4). However, it also includes varying amounts of other higher alkanes (ethane, propane), and a small percentage of carbon dioxide, nitrogen, hydrogen sulfide, or helium.

    826. Which of the following vitamins is generally excreted by human in urine?

    (1) Vitamin B 
    (2) Vitamin C
    (3) Vitamin D 
    (4) Vitamin E
    Answer:
    826. (*) More than one option is correct. All of the water-soluble vitamins such as Vitamin C
    and B vitamins (Thiamin, Riboflavin, Niacin, Pyridoxine, Cyanocobalamin and Pantothenic acid) are generally excreted by the human body through urine if they are in excess. These vitamins are absorbed by the digestive tract into the blood stream, metabolized and then excreted by the kidneys in the urine. Distinctly yellow urine may indicate excessive riboflavin (Vitamin B2) intake.

    827. Which of the following is used to make light weight, but strong plastic ?

    (1) Nylon
    (2) Polythene
    (3) Polyvinyl Chloride
    (4) Methyl Methacrylate
    Answer:
    827. (3) Polyvinyl chloride (PVC) is a common, strong but lightweight plastic that is used in making tough plastic. It is used for flexible applications such as insulating cables. It is the third-most widely produced synthetic plastic polymer, after polyethylene and polyprop-ylene.

    828. Which of the following is the correct sequence of countries in terms of maximum carbon dioxide emission?

    (1) China, USA, European Union, India
    (2) USA, India, China, European Union
    (3) China, India, European Union, USA
    (4) European Union, China, USA, India
    Answer:
    828. (1) According to the EDGAR database released by European Commission and Netherlands Environmental Assessment Agency in 2014, China, USA, European Union, India and Russia are the largest emitters of carbon emission (annual CO2 emissions estimates in thousands of CO2 tonnes) across the globe. Country O2 emissions (kt) in 2014 World 35,669,000 China 10,540,000 United States 5,334,000 European Union 3,415,000 India 2,341,000 Russia 1,766,000 Japan 1,278,000 Germany 767,000

    829. Which of the following substance’s smell is similar to Ethanoic acid?

    (1) Tomato juice 
    (2) Kerosene
    (3) Vinegar 
    (4) Lemon
    Answer:
    829. (3) Acetic acid, also known as ethanoic acid, is an organic chemical compound best recognized for giving vinegar its sour taste and pungent smell.Vinegar is roughly 3–9% acetic acid by volume, making acetic acid the main component of vinegar apart from water.

    830. Which of the following acids serves as an electrolyte in a lead storage battery?

    (1) Sulphuric acid
    (2) Lactic acid
    (3) Hydrochloric acid
    (4) Nitric acid
    Answer:
    830. (1) Dilute sulfuric acid (H2SO4) serves as the electrolyte in a lead-acid battery. Dilute sulfuric acid used for lead acid battery has ratio (to water) of 3:1 other components of the battery include: Lead peroxide (PbO2) and Sponge lead (Pb).

    831. Which of the following is not a natural source of hydrocarbon?

    (1) Natural Gas 
    (2) Coal
    (3) Petroleum 
    (4) Mica
    Answer:
    831. (4) There are three main natural sources of hydrocarbons: natural gas, petroleum and coal.Mica
    is a natural occurring mineral that is based on a collection of silicate minerals and composed of varying
    amounts of potassium, iron, aluminum, magnesium and water. It is widely used in the electrical industry.

    832. Helium is added to the oxygen supply of deep sea divers because it is

    (1) less poisonous than nitrogen
    (2) Lighter than nitrogen
    (3) Readily miscible with oxygen
    (4) less soluble in blood than nitrogen at high pressure
    Answer:
    832. (4) Deep-sea divers have their oxygen supply mixed with helium in order to avoid the toxic nature of oxygen under extreme pressures. The Helium atom is much smaller than the Nitrogen molecule, has a smaller electron cloud and is less polarizable. It, therefore, is less soluble in blood than nitrogen and prevents the formation of nitrogen bubbles in blood which blocks blood flow as the diver comes to the surface of the sea from underwater.

    833. Terylene is a condensation polymer of ethylene glycol and which acid?

    (1) Benzoic Acid
    (2) Salicylic acid
    (3) Phthalic acid
    (4) Terephthalic acid
    Answer:
    833. (4) Terylene is a co-polymer of ethylene glycol and Terephthalic acid. Also known as Dacron, it is prepared by the condensation polymerization of ethylene glycerol and Terephthalic acid with elimination of water. The reaction is carried out at about 420-460 K in the presence of a catalyst consisting of a mixture of zinc acetate and antimony trioxide.

    834. What are the components responsible for acid rain?

    (1) Nitrogen monoxide (NO) and Carbon monoxide (CO)
    (2) Sulphur dioxide (SO2) and Nitrogen oxides (NOx)
    (3) Carbon dioxide (CO2) and Carbon monoxide (CO)
    (4) Oxides of carbon (COx) and Oxides of nitrogen (NOx)
    Answer:
    834. (2)Acid rain is caused by emissions of sulfur dioxide (SO2) and nitrogen oxide (NOx), which react with the water molecules in the atmosphere to produce acids.The SO2 and NOX react with water, oxygen and other chemicals to form sulfuric and nitric acids.The chemicals in acid rain can cause paint to peel, corrosion of steel structures and weathering of stone buildings.

    835. What is Zeolite?

    (1) Hydrated Aluminosilicate
    (2) Hydrated Calcium Sulphate
    (3) Dehydrated Aluminosilicate
    (4) Dehydrated Calcium Sulphate
    Answer:
    835. (1) Zeolites are hydrated aluminosilicate minerals made from interlinked tetrahedra of alumina (AlO4) and silica (SiO4). In simpler words, they’re solids with a relatively open, three-dimensional crystal structure built from the elements aluminium, oxygen, and silicon, with alkali or alkaline-Earth metals (such as sodium, potassium, and magnesium) plus water molecules trapped in the gaps between them.

    836. L.P.G. is mostly liquefied

    (1) hydrogen 
    (2) oxygen
    (3) butane 
    (4) methane
    Answer:
    836. (3) Liquefied petroleum gas or liquid petroleum gas (LPG) is mostly propane (C3H8), or butane (C4H10). They are most commonly mixtures of these two hydrocarbon gases that are used as fuel in heating appliances, cooking equipment, and vehicles.In the northern hemisphere winter, the mixes contain more propane, while in summer, they contain more butane.

    837. What is used in storage batteries?

    (1) Copper 
    (2) Tin
    (3) Lead 
    (4) Zinc
    Answer:
    837. (3) The electrodes of the cells in a storage battery consist of lead grids. The openings of the anodic grid is filled with spongy (porous) lead. The openings of the cathodic grid is filled with lead dioxide (PbO2). Dilute sulfuric acid (H2SO4) serves as the electrolyte.Leadacid batteries, also known as lead storage batteries, can store a lot of charge and provide high current for short periods of time.

    838. The biogas used for cooking is a mixture of which of the following ?

    (1) Carbon dioxide and oxygen
    (2) Isobutane and propane
    (3) Methane and carbon monoxide
    (4) Methane and carbon dioxide
    Answer:
    838. (4) Biogas is essentially a mixture of Methane (CH4, around 55-75%) but also contains Carbon Dioxide (CO2), around 25-30%), varying quantities of Water (H2O) and Hydrogen Sulphide (H2S). Other compounds can also be found, especially in waste dump biogas: Ammonia (NH3), Hydrogen (H2), Nitrogen (N2) and Carbon Monoxide (CO). Methane is the valuable component under the aspect of using biogas fuel.

    839. _____ gives hardness to stainless steel.

    (1) Zinc 
    (2) Lead
    (3) Carbon 
    (4) Tin
    Answer:
    839. (3) Iron is alloyed with carbon lo make steel and has the effect of increasing the hardness and strength of iron. Pure iron cannot be hardened or strengthened by heat treatment but the addition of carbon enables a wide range of hardness and strength. High-carbon stainless steel contains a minimum of 0.3% carbon. The higher the carbon content, the less formable and the tougher the steel becomes.

    840. Which of the following is not soluble in water ?

    (1) Lead Sulphate
    (2) Zinc sulphate
    (3) Potassium sulphate
    (4) Sodium sulphate
    Answer:
    840. (2) Lead sulfate (PbSO4) is a white crystalline solid. It is insoluble in water and sinks in it. It is often seen in the plates/electrodes of car batteries, as it is formed when the battery is discharged. It is also known as fast white, milk white, sulfuric acid lead salt or anglesite.


    यह भी देखे :




















    Post a Comment

    0 Comments