Description : Glass is a – (1) pure solid (2) supercooled liquid (3) gel (4) polymer
Last Answer : (2) supercooled liquid Explanation: Glass is an amorphous (noncrystalline) solid material. Glasses are typically brittle and optically transparent. The standard definition of a glass (or vitreous solid ... is often used to describe any amorphous solid that exhibits a glass transition temperature Tg.
Description : Which of the following has pH value 7? (1) Pure Water (2) H2SO4 (3) Sodium Carbonate (4) HCl
Last Answer : (1) Pure Water Explanation: In chemistry, pH is a numeric scale used to specify the acidity or basicity of an aqueous solution. Solutions with a pH less than 7 are acidic and solutions with a pH greater than ... basic. Pure water is neutral, being neither an acid nor basic; so it has pH value of 7.
Description : Which of the following has pH value 7? (1) Pure Water (2) H2 SO4 (3) Sodium Carbonate (4) HCl
Last Answer : Pure Water
Description : Bagasse, a by-product of sugar manufacturing industry, is used for the production of - (1) Glass (2) Paper (3) Rubber (4) Cement
Last Answer : (2) Paper
Description : Portland cement manufactured from pure white chalk and clay but free from iron-oxide, is known as (A) Quick setting cement (B) Rapid hardening cement (C) White cement (D) Low heat Portland cement
Last Answer : Answer: Option C
Description : What is the element required for solar energy conversion? (1) Beryllium (2) Tantalum (3) Silicon (4) Ultra pure carbon
Last Answer : (3) Silicon Explanation: The most prevalent bulk material for solar cells is crystalline silicon (abbreviated as a group as c-Si), also known as "solar grade silicon". Bulk silicon is ... into multiple categories according to crystallinity and crystal size in the resulting ingot, ribbon, or wafer.
Description : What is the element required for solar energy conversion ? (1) Beryllium (2) Tantalum (3) Silicon (4) Ultra pure carbon
Last Answer : Silicon
Description : Hydrofluoric acid is not kept in glass bottles because it reacts with - (1) visible light (2) silicon dioxide of glass (3) aluminium oxide of glass (4) sodium oxide of glass
Last Answer : (2) silicon dioxide of glass
Description : Which one of the following substances does not have a melting point? (1) Bromine (2) Sodium chloride (3) Mercury (4) Glass
Last Answer : (3) Mercury Explanation: The boiling point is the temperature at which a material changes from a liquid to a gas (boils) while the melting point is the temperature at which a material changes from a solid to a liquid (melts).
Description : Glass is mainly composed of - (1) Sodium silicate (2) Calcium carbonate (3) Calcium hydroxide (4) Sodium bicarbonate
Last Answer : (1) Sodium silicate Explanation: Glass is made from silica (SiO₂) and soda lime, which react to form sodium silicate.
Description : Sodium calcium silicate is called _______. (1) Hard glass (2) Borosilicate glass (3) Soft glass (4) Jena glass
Last Answer : (3) Soft glass Explanation: Ordinary glass which is also known as soda glass or soft glass is a mixture of sodium silicate, Calcium silicate, and Silica.
Description : Which of the following substances is classified as amorphous? w) glass x) Zinc y) diamond z) sodium chloride
Last Answer : ANSWER: W -- GLASS
Description : is tap water in a glass pure substances or mixture?
Last Answer : Are a mixture because is water is a compound of hydrogen and oxygen
Description : What is the ounces of pure alcohol in a 6 oz glass of wine with a proof value of 24?
Last Answer : This question is impossible to answer.
Description : Ice cubes are added to a glass of pure water and a glass of pure alcohol. The ice would be – (1) at a higher level in water (2) at a higher level in alcohol (3) at the same level in both (4) floating in alcohol and sinking in water
Last Answer : (1) at a higher level in water Explanation: Density of water is approx 1 g/ml; Density of Ice is approx 0.93g/ml; and Density of 100% pure ethanol is 0.79g/ml. So the density of ice cubes is lesser than water, but higher than alcohol. So it will float in water, but sink in alcohol.
Description : Which of the listed groups of electrical insulation materials is best suited for the highest operating temperatures? A. impregnated cotton and silk B. unimpregnated paper and cotton C. pure glass and quartz D. mica and porcelain with bonding agents
Last Answer : Answer: C
Description : Silica (pure glass) fibers are used because of their low intrinsic material absorption at the wavelengths of operation. This wavelength of operation is between two intrinsic absorption regions. What are these two regions called? What are the wavelengths of operation for these two regions?
Last Answer : Ultraviolet absorption region (below 400 nm) and infrared absorption region (above 2000 nm).
Description : Ice cubes are added to a glass of pure water and a glass of pure alcohol. The ice would be (1) at a higher level in water (2) at a higher level in alcohol (3) at the same level in both (4) floating in alcohol and sinking in water
Last Answer : at a higher level in water
Description : If a sample of pure sodium has a mass of 8.2 grams and sodium has an average atomic mass of 22.99 gmol how many sodium atoms are there in the sample?
Last Answer : Need answer
Description : What is a mixture of Potassium Nitrate Powdered Charcoal and Sulphur called? A. Paint B. Glass C. Gun Powder (Answer) D. Cement
Last Answer : C. Gun Powder (Answer)
Description : Which of the following is the most widely used heat insulating material for pipelines carrying steam? (A) Tar dolomite bricks followed by asbestos (B) Fireclay refractory followed by aluminium sheet (C) Cotton followed by aluminium foil (D) 85% magnesia cement and glass wool
Last Answer : (D) 85% magnesia cement and glass wool
Description : Salt is the basic raw material for the manufacture of (A) Cement (B) Glass (C) Potteries (D) Caustic soda
Last Answer : (D) Caustic soda
Description : Maximum consumption of limestone is in the __________ industry. (A) Iron and steel (B) Cement (C) Glass (D) Fertiliser
Last Answer : (D) Fertiliser
Description : For constructing a terrazzo floor, Pick up the incorrect statement from the following: (A) A base course is prepared as in cement concrete flooring (B) A 32 mm thick layer of cement concrete ... final grinding is over, oxalic acid mixed with water is spread over and rubbed hard with soft material
Last Answer : Answer: Option B
Description : Which of the following is NOT a characteristic of glass ionomer cements? a. strong in compression but weaker in tension True b. the matrix is formed during the initial set of the cement c. sets via ... for at least 24 hours true d. suitable for use as a core build up material in anterior teeth
Last Answer : d. suitable for use as a core build up material in anterior teeth
Description : Etching a hybrid glass ionomer-composite a. is necessary for composite resin bonding b. is not necessary for composite resin bonding c. is necessary for adding a glass ionomer cement for repair ... glass ionomer cement for repair e. a 3-5 second etch with 10% phosphoric acid is recommended
Last Answer : b. is not necessary for composite resin bonding
Description : lass Ionomer Cement sets because of,** A. Acid-Base reaction B. Addition polymerisation reaction C. Growth of glass crystals D. Slip plane locking E. Solvent evaporation
Last Answer : A. Acid-Base reaction
Description : Main constituents of Portland cement are calcium aluminate and (A) Gypsum (B) Silicates (C) Sodium silicate (D) Carbonates
Last Answer : (B) Silicates
Description : The fluid generally used for grouting is (A) Cement and water mix (B) Clay suspension (C) Sodium silicate (D) All the above
Last Answer : (D) All the above
Description : Setting time of cement increases by adding (A) Gypsum (B) Hydrogen peroxide (C) Calcium chloride (D) Sodium oxide
Last Answer : Answer: Option A
Description : Cement paints usually (A) Contain hydrated lime (B) Contain 5% to 10% colour pigments (C) Contain 5% sodium chloride (D) All the above
Last Answer : Answer: Option D
Description : Setting time of cement increases by adding (i)gypsum (ii)sodium oxide (iii)calcium chloride [ A ] i [ B ] i and ii [ C ] i and iii [ D ] i, ii and iii
Last Answer : [ A ] i
Description : The element with highest first ionization energy is - (1) hydrogen (2) helium (3) lithium (4) sodium
Last Answer : (2) helium Explanation: The first ionisation energy is the energy required to remove the most loosely held electron from one mole of gaseous atoms to produce 1 mole of gaseous ions each with a charge of ... ) of Hydrogen: around 1200: Helium: about 2500; Lithium: about 500; and Sodium: about 500.
Description : The most electronegative element among the following is - (1) sodium (2) bromine (3) fluorine (4) oxygen
Last Answer : (3) fluorine Explanation: Fluorine is the most electronegative element, while francium is one of the least electronegative.
Description : The most electronegative element among the following is – (1) Fluorine (2) Sodium (3) Chlorine (4) Oxygen
Last Answer : (1) Fluorine Explanation: Electronegativity of the elements using the Pooling Scale is as follows: Fluorine: 3.98, Oxygen: 3.44, Chlorine: 3.16, and Sodium: 0.93. Electronegativity increases down the group and decreases down the period.
Description : The element used for making solar cells is - (1) Magnesium (2) Sodium (3) Calcium (4) Silicon
Last Answer : (4) Silicon Explanation: Materials presently used for photovoltaic solar cells include mono-crystalline silicon, polycrystaijhne silicon, amorphous silicon, cadmium telluride, and copper indium selenideisulfide.
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 : 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 : The most electronegative element among the following is (1) Fluorine (2) Sodium (3) Chlorine (4) Oxygen
Last Answer : Fluorine
Description : The element used for making solar cells is (1) Magnesium (2) Sodium (3) Calcium (4) Silicon
Description : The element with highest first ionisation energy is (1) hydrogen (2) helium (3) lithium (4) sodium
Last Answer : helium
Description : What is a pure substance whose smallest unit is made of atoms of more than one element?
Last Answer : Compound
Description : Is charcoal black a element pure compound or a mixture?
Last Answer : This is the element carbon.
Description : The element required for Solar energy conversion - (1) Beryllium (2) Silicon (3) Tantalum (4) Ultra pure carbon
Last Answer : (2) Silicon Explanation: Energy conversion. n. (General Physics) is the process of changing one form of energy into another, such as nuclear energy into heat or solar energy into electrical energy.
Description : Necessary element of change in solar energy to electric energy – (1) Berilliurn (2) Silicon (3) Tantelum (4) Pure Copper
Last Answer : (2) Silicon Explanation: A small solar electric or photovoltaic (PV) converts solar energy into electrical energy. Solar cells consist of semiconductor materials which work on photoelectric effect. Silicon remains the most popular material for solar cells.
Description : What is the element required for solar energy conversion ---? A. Ultra pure carbon B. Silicon (Answer) C. Beryllium D. Tantalum
Last Answer : B. Silicon (Answer)
Description : Product is a k t is a key element in _____. At one extreme, it m e, it may consist of pure tangible goods or at the other extreme pure services. a. market offering b. brand equity brand equity c. brand extension d. co-branding
Last Answer : a. market offering
Description : Necessary element of change in solar energy to electric energy (1) Berillium (2) Silicon (3) Tantelum (4) Pure Copper
Description : Take a 250 mL beaker/glass tumbler. Fill half of it with water. Now carefully cut a small piece of sodium metal. Dry it using filter paper and wrap it in a small piece of cotton. Put the sodium piece wrapped in cotton into the beaker. Observe carefully. -Science
Last Answer : On touching the beaker, it was felt hot. The solution turns the red litmus paper to blue which shows it is basic in nature. Blue litmus paper do not show any colour change with the solution.
Description : What happens when: a) When a mixture of sodium acetate and soda lime is heated in a hard glass test tube.
Last Answer : Methane gas is evolved. CH 3 COONA + NaOH CaO Na 2 CO 3 + CH 4 b) Methane is burnt in air or oxygen or methane undergoes complete combustion. It forms carbon dioxide and water. CO 2 + H ... ultraviolet light (sunlight). Organic product chloromethane is formed CH 4 + Cl 2 UV CH 3 Cl + HCl