Description : There are two elements calcium (atomic number 20) and argon (atomic number 18) The mass number of both the elements is 40. They are therefore known as (a) isotones (b) isochores (c) isobars (d) isotopes
Last Answer : Ans:(c)
Description : Which one of the following best defines the word allotropes ? A Different structural forms of an element B A pair of substances that differ by H+ C Elements that possess properties intermediate between ... a specific number of neutrons E The different phases (solid, liquid or gas) of a substance
Last Answer : A Different structural forms of an element
Description : The mass spectrograph directly yields a value for which one of the following? w) mass of a photon x) mass of a neutron y) masses of isotopes of elements z) mass to charge ratio of ions
Last Answer : ANSWER: Z -- MASS TO CHARGE RATIO OF IONS
Description : The three isotopes of hydrogen are protium, tritiu and: w) heprin x) helium y) duodenum z) deuterium
Last Answer : ANSWER: Z -- DEUTERIUM
Description : Isotopes of an element have different numbers of: w) electrons x) protons y) neutrons z) leptons
Last Answer : ANSWER: Y -- NEUTRONS
Description : The neutrons in an atom: w) are part of the nuclear charge x) rotate about the nucleus in elliptical orbits y) vary in number with different isotopes z) are always equal in number to the total number of protons
Last Answer : ANSWER: Y -- VARY IN NUMBER WITH DIFFERENT ISOTOPES
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 : Which of the following elements forms a tetrahedra structure? w) carbon x) beryllium y) boron z) fluorine
Last Answer : ANSWER: W -- CARBON
Description : Most of the new atoms formed when atoms in a nuclear reactor capture neutrons without fissioning are: w) fission products x) activation products y) actinides z) lead isotopes
Last Answer : ANSWER: Y -- ACTINIDES
Description : The internal structure of crystals was first studied with which of the following? w) x-rays x) isotopes y) electron microscopes z) lasers
Last Answer : ANSWER: W -- X-RAYS
Description : At room temperature, most elements are in which phase of matter? w) solid x) liquid y) gas z) plasma
Last Answer : ANSWER: W -- SOLID
Description : The existence of an element in two or more forms i the same physical phase is known as: w) allotropy x) diphasisty y) polyformation z) diatomic existence
Last Answer : ANSWER: W -- ALLOTROPY
Description : Immiscible liquids: w) are not mutually soluble x) dissolve in each other y) dissolve in more than one liquid z) are unstable and chemically react e) do not exist
Last Answer : ANSWER: W -- ARE NOT MUTUALLY SOLUBLE
Description : The element which shows large number of allotropes among VIA group elements
Last Answer : The element which shows large number of allotropes among VIA group elements A. S B. Se C. Po D. Te
Description : Elements that show the properties of both metals and non-metals are called (a) Allotropes (b) Metalloids (c) Alloys (d) Colloids
Last Answer : Ans:(b)
Description : The lanthanide series elements are also known as: w) rare earth elements x) non-metals y) fifth period elements z) sixth period elements
Last Answer : ANSWER: W -- RARE EARTH ELEMENTS
Description : A negative heat of solution indicates that: w) an endothermic dissolving process occurs x) solute solubility increases with rising solution temperature y) solute solubility decreases with rising solution temperature z) super-saturation conditions exist
Last Answer : ANSWER: Y -- SOLUTE SOLUBILITY DECREASES WITH RISING SOLUTION TEMPERATURE
Description : What are minimum boiling azeotropes? Give one example?
Last Answer : Ans:- A mixture which boils at temp. lower than boiling point of its components the mixture is known as minimum boiling azeotropes. E.g water and Benzene.
Description : What are maximum boiling azeotropes? Give one example?
Last Answer : Ans:- A mixture which boils at temp. brighter than the boiling point of its components the mixture is known as maximum boiling azeotropes. Eg- a mixture of HCl and H2O containing 20.2% of HCl by weight.
Description : Molecular oxygen is said to be paramagnetic. This indicates that molecular oxygen: w) is a gas at room temperature x) forms molecules containing two oxygen atoms y) has an approximate molecular weight of 32 z) has unpaired electrons
Last Answer : ANSWER: Z -- HAS UNPAIRED ELECTRONS
Description : Which of the following substances is a molecular solid? w) Glass x) Ice y) Silver z) Table Salt
Last Answer : ANSWER: X -- ICE
Description : The process of a solid converting directly into a gas is called: w) fusion x) sublimation y) condensation z) distillation
Last Answer : ANSWER: X -- SUBLIMATION
Description : The energy required to melt one mole of a solid at its melting point is called one of the following. w) the molar heat of fusion x) the molar hear of vaporization y) the molar heat of capacity z) the melting point
Last Answer : ANSWER: W -- THE MOLAR HEAT OF FUSION
Description : The critical temperature is the temperature: w) above which a substance cannot be vaporized x) at which the density is a minimum y) at which solid, liquid, and vapor are in equilibrium z) above which the substance cannot be liquified.
Last Answer : ANSWER: Z -- ABOVE WHICH THE SUBSTANCE CANNOT BE LIQUIFIED.
Description : Which one of the following is classified as a covalent network solid crystal? w) CaO x) SiO2 y) CO2 z) Pb
Last Answer : ANSWER: B -- SiO2
Description : Dry ice is the solid form of what gas? w) nitrogen x) oxygen y) helium z) carbon dioxide
Last Answer : ANSWER: Z -- CARBON DIOXIDE
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 : Which of the following substances is an ionic netw solid? w) Diamond x) Table Salt y) Brass z) Dry ice
Last Answer : ANSWER: X -- TABLE SALT
Description : A net ionic equation does NOT show: w) electronic charges x) solid products (precipitates) y) spectator ions z) reacting species
Last Answer : ANSWER: Y -- SPECTATOR IONS
Description : Which of the following metals is a solid at room temperature, yet melts in your hand? w) gallium x) cesium y) sodium z) magnesium
Last Answer : ANSWER: W -- GALLIUM
Description : Which of the following forms the weakest acid in aqueous solution? w) hydrogen fluoride x) hydrogen chloride y) hydrogen bromide z) hydrogen iodide
Last Answer : ANSWER: W -- HYDROGEN FLUORIDE
Description : What is the name given to the non-superimposable mirror image forms of chiral compounds? w) cis-trans x) enantiomers y) functional isomers z) diasteriomers
Last Answer : ANSWER: X -- ENANTIOMERS
Description : Reaction between X and Y forms compound Z. X loses electron and Y gains electron. Which of the following properties is not shown by Z? A) Has high melting point B) Has low melting point C) Conducts electricity in molten state D) Occurs as solid
Last Answer : B) Has low melting point
Description : The molar volume of which two elements is the same at standard temperature and pressure? w) fluorine and bromine x) fluorine and iodine y) fluorine and chlorine z) bromine and iodine
Last Answer : ANSWER: Y -- FLUORINE AND CHLORINE
Description : Which of the following elements is not an alkaline earth metal? w) beryllium x) barium y) calcium z) rubidium
Last Answer : ANSWER: Z -- RUBIDIUM
Description : Most of the transuranic elements were first created: w) in Germany x) at Argonne National Laboratory y) in California z) in Russia
Last Answer : ANSWER: Y -- IN CALIFORNIA
Description : Which of the following elements does not occur in nature as a native ore? w) silver x) gold y) platinum z) aluminum
Last Answer : ANSWER: Z -- ALUMINUM
Description : Which of the following elements does not normally occur as a diatomic molecule? w) hydrogen x) chlorine y) argon z) oxygen
Last Answer : ANSWER: Y -- ARGON
Description : Radon differs from other naturally radioactive elements in which one of the following ways. Is it because radon w) is extremely radioactive x) decays into the element radium y) is a noble gas z) is as chemically active as fluorine
Last Answer : ANSWER: Y -- IS A NOBLE GAS
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 : Which of the 3rd period elements loses electrons most readily? w) Sodium x) Magnesium y) Aluminum z) Silicon
Last Answer : ANSWER: A-SODIUM
Description : What are the major constituents of typical fly ash particles generated from the combustion of coal? w) acidic and basic oxides x) trace elements y) unburned carbon z) sulfates and phosphates
Last Answer : ANSWER: W -- ACIDIC AND BASIC OXIDES
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 elements has the highest first ionization energy? w) Helium x) Neon y) Fluorine z) Argon
Last Answer : ANSWER: W -- HELIUM
Description : Which of the following elements would form a covalent bond with Bromine? w) Calcium x) Aluminum y) Oxygen z) Tin
Last Answer : ANSWER: Y -- OXYGEN
Description : Which of the following elements has the largest crystallographic radius? w) Mg x) N y) K z) F
Last Answer : ANSWER: Y -- K
Description : Which one of the following elements is not found in nature? w) Technetium x) Iridium y) Osmium z) Molybdenum
Last Answer : ANSWER: W -- TECHNETIUM
Description : Which of the following elements gains electrons most readily? w) Sodium x) Magnesium y) Aluminum z) Fluorine
Last Answer : ANSWER: D -- FLUORINE
Description : Which of the following elements has the highest electronegativity? w) Lithium x) Iodine y) Cesium z) Oxygen
Last Answer : ANSWER: D -- OXYGEN