Description : In vulcanization, natural rubber is heated with- (1) Carbon (2) Sulphur (3) Silicon (4) Phosphorus
Last Answer : (2) Sulphur Explanation: Vulcanization of rubber is a process of improvement of the rubber elasticity and strength by heating it in the presence of sulfur, which results in three-dimensional crosslinking of the chain rubber molecules (polyisoprene) bonded to each other by sulfur atoms.
Description : Which one of the following molecules exhibits resonance? w) Carbon Tetrachloride x) Carbonate ion y) Sulfur Dichloride z) Phosphorus Tribromide
Last Answer : ANSWER: X -- CARBONATE ION
Description : Which of the following substances would be the best choice to neutralize sulfuric acid? w) sodium hydroxide x) silicon dioxide y) copper metal z) phosphorus pentoxide
Last Answer : ANSWER: W -- SODIUM HYDROXIDE
Description : Which of the following groups of elements have an OUTER ELECTRONIC configuration of S-2-P-2? w) halogens x) Nitrogen-Phosphorus Group y) Carbon-Silicon Group z) Boron-Aluminum Group
Last Answer : ANSWER: Y -- CARBON-SILICON GROUP
Description : Which of the following substances would be the best choice to neutralize aqueous Sodium Hydroxide? w) sodium carbonate x) silicon dioxide y) aluminum oxide z) phosphorus pentoxide
Last Answer : ANSWER: Z -- PHOSPHORUS PENTOXIDE
Description : Vulcanization is the process of cross-linking polymer chains in rubber using (a) Sulfur. (b) Formaldehye. (c) Benzoyl peroxide. (d) Ethylene glycol.
Last Answer : Sulfur.
Description : Vulcanization of rubber is carried out by adding (1) Sulphur (2) Carbon (3) Ozone (4) Phosphorus
Last Answer : Sulphur
Description : Which compound is responsible for the rotten egg smell? w) sulfuric acid x) putrescine y) hydrogen sulfide z) sulfur dioxide
Last Answer : ANSWER: Y -- HYDROGEN SULFIDE (NOTE: putrescine is a real compounz)
Description : Which of the following is the element which makes up about 8 percent of the earth's crust and occurs in all rocks except limestone and sandstone? w) sulfur x) aluminum y) sodium z) magnesium
Last Answer : ANSWER: X -- ALUMINUM
Description : What device is used to remove sulfur dioxide from power plant stack gases? w) scrubber x) precipitator y) digester z) clarifier
Last Answer : ANSWER: W -- SCRUBBER
Description : The hydrocarbon end of a detergent molecule is: w) hydrophilic x) hydrophobic y) possible ionic z) contains oxygen or sulfur
Last Answer : ANSWER: HYDROPHOBIC
Description : Which of the following is the primary reason for adding calcium carbonate to the reduction process of iron oxide ores ? The calcium carbonate: w) acts as an oxidizing agent x) removes silicate waste products y) acts as a reducing agent z) removes sulfur waste products
Last Answer : ANSWER: X -- REMOVES SILICATE WASTE PRODUCTS
Description : One source of Acid Rain is: w) sulfur in fossil fuels x) carbon in coal y) hydrogen in hydrocarbons z) chloroflorocarbons in aerosols
Last Answer : ANSWER: W -- SULFUR IN FOSSIL FUELS
Description : The element used in treating manic depression is: w) sulfur x) nitrogen y) calcium z) lithium
Last Answer : ANSWER: Z -- LITHIUM
Description : Which of the following materials are used in the manufacture of pig iron from iron ore? w) Limestone and carbon x) Calcium oxide and oxygen y) Chromium and nickel z) Oxygen and sulfur dioxide
Last Answer : ANSWER: W -- LIMESTONE AND CARBON
Description : Which of the following are alloying materials used the manufacture of stainless steel? w) Limestone and carbon x) Calcium oxide and oxygen y) Oxygen and sulfur dioxide z) Chromium and nickel
Last Answer : ANSWER: Z -- CHROMIUM AND NICKEL
Description : Which of the following elements can form the great number of covalent bonds? w) carbon x) nitrogen y) oxygen z) sulfur
Last Answer : ANSWER: Z -- SULFUR
Description : In the filling of electron orbitals for the elemen sulfur, which has 16 electrons, the number of electrons in the 3p orbitals is: w) 3 x) 4 y) 6 z) 0
Last Answer : ANSWER: X -- 4
Description : Which of the following elements would form an acid oxide with the formula XO2 and an acidic compound with hydrogen with the formula XH2? w) Sodium x) Magnesium y) Aluminum z) Sulfur
Description : Cinnabar, pyrite and galena are minerals which consist of one or more metals combined with the same element. Which one of the following is the element that is common to all three of these minerals? Is it: w) iron x) copper y) sulfur z) sodium
Last Answer : ANSWER: C-- SULFUR
Description : Which one of the following elements is least likely to be found in commercial fertilisers? (1) Nitrogen (2) Phosphorus (3) Potassium (4) Silicon
Last Answer : (4) Silicon Explanation: Commercial Fertilizers - a substance containing one or more recognized plant nutrients and that is used for its plant nutrient content or that is designated for use or claimed to have value in promoting plant growth.
Description : Of the nonmetallic elements the one least likely to be found in organic compounds is: w) nitrogen x) phosphorus y) chlorine z) selenium
Last Answer : ANSWER: Z -- SELENIUM
Description : What is the only nonmetal element that is a liquid room temperature? w) phosphorus x) bromine y) iodine z) arsenic
Last Answer : ANSWER: X -- BROMINE
Description : Allotropic modifications of phosphorus include each of the following EXCEPT: w) red phosphorus x) black phosphorus y) white phosphorus z) green phosphorus
Last Answer : ANSWER: Z -- GREEN PHOSPHORUS
Description : An organic compound (A) has a molecular weight 78 and an empirical formula CH. (A) is resistant to attack by oxidizing agents but undergoes substitution and addition reactions. X-ray analysis shows that the ... suggests that compound (A) is (a) Benzene (b) Cyclohexane (c) Toluene (d) n-Hexane
Last Answer : Benzene
Description : Which of the following quantities has the GREATEST influence on the overall efficiency of a conventional (Rankine cycle) electric generating station burning fossil fuels? w) steam temperature at the steam turbine ... pressure at the steam turbine inlet z) pounds of ash and sulfur per pound of fuel
Last Answer : ANSWER: W -- STEAM TEMPERATURE AT THE STEAM TURBINE INLET
Description : Global climate change is being attributed to the atmospheric increase in what two gases produced by human activities? w) ozone and methane x) nitrous oxide and sulfur dioxide y) methane and carbon dioxide z) ozone and carbon monoxide
Last Answer : ANSWER: Y -- METHANE AND CARBON DIOXIDE
Description : Waste gases from industrial plants form acids that hasten chemical weathering. Most of the gases are compounds of: w) argon x) hydrogen y) iron z) sulfur
Description : The principal volcanic gas (in terms of quantity) is: w) carbon dioxide x) nitrogen dioxide y) sulfur dioxide z) steam (H2O)
Last Answer : ANSWER: Z -- STEAM (H2O)
Description : Diamond and graphite are polymorphs of which of th following elements? w) magnesium x) carbon y) sulfur z) nitrogen
Last Answer : ANSWER: X -- CARBON
Description : Which of the following gases is given off in the acid test of a carbonate mineral? w) chlorine x) nitrogen y) carbon dioxide z) sulfur dioxide
Last Answer : ANSWER: Y -- CARBON DIOXIDE
Description : Global climate change is being attributed to the atmospheric increase in what two gases produced by human activities? w) oxygen and hydrogen x) ozone and methane y) nitrous oxide and sulfur dioxide z) methane and carbon dioxide e) ozone and carbon monoxide
Last Answer : ANSWER: Z -- METHANE AND CARBON DIOXIDE
Description : Which of the following is not a major pollutant from automobiles. w) carbon monoxide x) unburned hydrocarbons y) nitrous oxide z) sulfur dioxide
Last Answer : ANSWER: Z -- SULFUR DIOXIDE
Description : Which of the following is believed to be responsible for the hole in the ozone layer over Antarctic? w) carbon dioxide x) compounds containing sulfur y) radioactivity z) compounds containing chlorine
Last Answer : ANSWER: Z -- COMPOUNDS CONTAINING CHLORINE
Description : Which of the following elements was unknown to ancient civilizations? w) tin x) aluminum y) mercury z) sulfur
Description : In the United States, low sulfur coal can be found primarily in the: w) northeast x) southeast y) midwest z) west
Last Answer : ANSWER: Z -- WEST
Description : Which of the 3rd period elements loses electrons most readily? w) Sodium x) Magnesium y) Aluminum z) Silicon
Last Answer : ANSWER: A-SODIUM
Description : Mendeleev proposed the existence of an unknown element that he called eka-aluminum. The element is now called: w) magnesium x) silicon y) gallium z) germanium
Last Answer : ANSWER: C -- GALLIUM
Description : Which of the following elements would most likely be a silvery solid at room temperature? w) Sodium x) Silicon y) Selenium z) Astatine
Last Answer : ANSWER: W -- SODIUM
Description : In which form is Silicon most frequently found in nature? w) The free element Silicon x) Silicon-Oxygen compounds y) Silicon-Carbon compounds z) Silicon-Metal compounds
Last Answer : ANSWER: X -- SILICON-OXYGEN COMPOUNDS
Description : Which of the following is not a covalent network solid? w) silicon dioxide x) silicon oxide y) boron nitrate z) sodium oxide
Last Answer : ANSWER: D -- SODIUM OXIDE
Description : The element least likely to be found in an organic compound is (a) oxygen (b) sulfur (c) nitrogen (d) silicon
Last Answer : silicon
Description : What is the only non-metal element that is a liquid at room temperature and one atmosphere? w) bromine x) argon y) silicon z) selenium
Last Answer : ANSWER: W -- BROMINE
Description : Which of the following elements is found in the earth's crust as both a native element and as a compound? w) argon x) copper y) chlorine z) silicon
Last Answer : ANSWER: X -- COPPER
Description : Which of the following materials is the hardest? w) calcite x) silicon carbide y) topaz z) quartz
Last Answer : ANSWER: X -- SILICON CARBIDE
Description : Steel is composed of a number of elements. The two essential elements are iron and w) aluminum x) carbon y) nickel z) silicon
Description : Phenomena in which signal transmitted in one circuit creates undesired effect in other circuit is known as A. crosstalk B. signal attenuation C. sampling D. crosslinking
Last Answer : crosslinking
Description : Vinca alkaloids exert antitumor activity by: A. Activating topoisomerase II to cause breaks in DNA strands B. Crosslinking DNA strands C. Inhibiting DNA mediated RNA synthesis D. Inhibiting polymerization of tubulin to form intracellular microtubules
Last Answer : D. Inhibiting polymerization of tubulin to form intracellular microtubules
Description : A reduction reaction always involves the: w) loss of electrons x) gain of electrons y) addition of oxygen z) removal of oxygen
Last Answer : ANSWER: X -- GAIN OF ELECTRONS