Description : The radioactive element most commonly detected in humans is: w) potassium-40 x) cobalt-60 y) iodine-131 z) plutonium-238
Last Answer : ANSWER: W -- POTASSIUM-40
Description : What radioactive element is routinely used in treating hyperthyroidism, and in reducing thyroid activity? w) Iron-59 x) Gold-198 y) Cobalt-60 z) Iodine-131
Last Answer : ANSWER: Z -- IODINE-131
Description : If you start with 24 grams of a radioactive element with a half-life of one month, how many grams of the radioactive element will be left after 2 months? w) 1.5 grams x) 3 grams y) 6 grams z) 12 grams
Last Answer : ANSWER: Y -- 6 GRAMS
Description : In a spent fuel assembly, the radioactive elements having the longest half-lives are the: w) fission products x) actinides y) activation products z) radioisotopes of lead
Last Answer : ANSWER: X -- ACTINIDES
Description : A colligative property depends on: w) chemical properties of particles in system x) physical properties of particles in system y) number of particles present in system z) all of the above
Last Answer : ANSWER: Y -- NUMBER OF PARTICLES PRESENT IN SYSTEM
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 : (A) Nuclear isomers have same atomic number and same mass number but with different radioactive properties. `U_((A))` and `U_((Z))` are nuclear isomer
Last Answer : (A) Nuclear isomers have same atomic number and same mass number but with different radioactive properties. `U_ ... both (A) and (R ) are incorrect.
Description : The binding energy of a nucleus is defined as one of the following. Is this definition: w) the energy equivalent to its mass x) the mass difference between its neutrons and protons y) the energy ... the difference between the mass of the nucleus and the sum of the masses of its protons and neutrons
Last Answer : ANSWER: Z -- THE DIFFERENCE BETWEEN THE MASS OF THE NUCLEUS AND THE UM
Description : For a substance, density, solubility and melting point are examples of: w) physical properties x) amorphous properties y) chemical properties z) potential properties
Last Answer : ANSWER: W -- PHYSICAL PROPERTIES
Description : Which of the following has the smallest atomic radius? w) iodine x) chlorine y) fluorine z) bromine
Last Answer : ANSWER: Y -- FLUORINE
Description : Which of the following molecules is polar? w) Iodine x) Carbon Dioxide y) Carbon Monoxide z) Chlorine
Last Answer : ANSWER: Y -- CARBON MONOXIDE
Description : Which of the following substances would be expecte to have the highest melting point? w) Potassium Bromide x) Iodine y) Methane z) Hydrogen Chloride
Last Answer : ANSWER: W -- POTASSIUM BROMIDE
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 : Which of the following elements has the highest electronegativity? w) Lithium x) Iodine y) Cesium z) Oxygen
Last Answer : ANSWER: D -- OXYGEN
Description : Which of the following halogens does NOT replace the other halogens from their compounds? w) fluorine x) iodine y) bromine z) chlorine
Last Answer : ANSWER: X -- IODINE
Description : Compounds of iodine are NOT used for which of the following? w) as a refrigerant x) in photographic film y) as an essential part of diet z) as an antiseptic
Last Answer : ANSWER: W -- AS A REFRIGERANT
Description : The nuclei of heavy atoms generally contain: w) more electrons than neutrons x) more protons than electrons y) more neutrons than electrons z) more orbitals than electrons
Last Answer : ANSWER: Y -- MORE NEUTRONS THAN ELECTRONS
Description : The silver luster of the metals can be attributed to one of the following. It is attributed to their free w) protons x) ions y) neutrons z) electrons
Last Answer : ANSWER: Z -- ELECTRONS
Description : It is believed that carbon-14 in nature is slowly generated by the action of: w) protons on carbon-12 x) electrons on hydrogen y) cosmic rays on boron z) neutrons on nitrogen
Last Answer : ANSWER: Z -- NEUTRONS ON NITROGEN
Description : Which of the following terms refers to a material which slows neutrons? w) retarder x) moderator y) buffer z) bottleneck
Last Answer : ANSWER: X -- MODERATOR
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 : Lead-206 is the final product of the radioactive decay series named the: w) thorium series x) actinium series y) uranium series z) neptunium series
Last Answer : ANSWER: Y -- URANIUM SERIES
Description : Radioactive decay is a: w) zero-order process x) temperature-dependent process y) first-order process z) second-order process
Last Answer : ANSWER: Y -- FIRST-ORDER PROCESS
Description : Which of the following scientists was awarded the Nobel Prize in 1911 for the discovery of the radioactive elements, radium and polonium? w) John Dalton x) Dmitri Mendeleev y) Emil Fischer z) Marie Curie
Last Answer : ANSWER: Z -- MARIE CURIE
Description : What happens to the period of a pendulum if the mass of the bob is quadrupled? w) it is cut in half x) it stays the same y) it is doubled z) it is quadrupled
Last Answer : ANSWER: X -- IT STAYS THE SAME
Description : If the distance between the centers of mass of two bodies is doubled, the gravitational force between the bodies will become what portion of the original force: w) double x) one half y) remain the same z) one quarter
Last Answer : ANSWER: Z -- ONE QUARTER
Description : A sphere which has half the radius but twice the density of another sphere has: w) more mass x) less mass y) the same mass z) the same weight
Last Answer : ANSWER: X -- LESS MASS
Description : A satellite of mass "M" is in orbit around the earth. If a second satellite of mass "2M" is to be placed in the same orbit, the second satellite must have a velocity which is: w) half ... first satellite y) twice the velocity of the first satellite z) four times the velocity of the first satellite
Last Answer : ANSWER: X -- THE SAME AS THE VELOCITY OF THE FIRST SATELLITE
Description : The half-life of an isotope of an element is 5 days. The mass of a 10 gram sample of this isotope remaining after 20 days is: w) 0.312 grams x) 0.625 grams y) 1.25 grams z) 2.50 grams
Last Answer : ANSWER: X -- 0.625 GRAMS
Description : The atomic masses of three elements X, Y and Z having similar chemical properties are 7, 23 and 39 respectively. a) Calculate the average atomic mass of elements X and Z. b) How is the ... this example? d) Give another example of a set of elements which are classified according to this law.
Last Answer : a) The average atomic mass of X and Z = 7 39 2 46 2 23 b) The average atomic mass of X and Z is equal to the atomic mass of Y c) The law illustrated in this example is Dobereiner’s law of triads. d) Another example of Dobereiner’s law is Calcium, Strontium and Barium.
Description : Refractory metals are known for which of the following properties: w) lack of chemical reactivity x) low density y) high melting point z) high thermal conductivity
Last Answer : ANSWER: Y -- HIGH MELTING POINT
Description : What two primary factors determine whether or no molecular collision leads to a chemical reaction? w) energy and volume of molecules x) energy and mass of molecules y) energy and orientation of molecules z) orientation and volume of molecules
Last Answer : ANSWER: Y -- ENERGY AND ORIENTATION OF MOLECULES
Description : In the fission of U235, what is the average number of neutrons produced in the fission reaction? w) 1.5 x) 2.5 y) 3.5 z) 4.5
Last Answer : ANSWER: X -- 2.5
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 : The dominant charge carriers in p-type semiconductors are: w) neutrons x) electrons y) protons z) holes
Last Answer : ANSWER: Z -- HOLES
Description : Photoelectric electricity is produced directly from solar energy when which of the following are absorbed in a semiconductor to create an electric current? w) protons x) electrons y) neutrons z) photons
Last Answer : ANSWER: Z -- PHOTONS
Description : The ability of an atom to absorb neutrons is its neutron capture cross section. The unit of measurement for neutron capture cross section is: w) the nucleus volume x) capture capacity y) resonance quotient z) barn
Last Answer : ANSWER: Z -- BARN
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 : A fast reactor uses: w) an extremely short time to get to the maximum operating reactivity. x) uranium-235 as fuel. y) heavy water as a coolant. z) essentially unmoderated neutrons.
Last Answer : ANSWER: Z -- ESSENTIALLY UNMODERATED NEUTRONS.
Description : Reactors in commercial nuclear power plants in the U.S. are often referred to as thermal reactors. A thermal reactor uses: w) fissionable plutonium-239 as fuel. x) a relatively low heat output. y) neutrons moderated to relatively low energies. z) liquid sodium as a coolant.
Last Answer : ANSWER: Y -- NEUTRONS MODERATED TO RELATIVELY LOW ENERGIES.
Description : Of the following, which non-fissioning element is used in the cooling water of nuclear power plants to help control the rate of the fission reaction by absorbing neutrons: w) zirconium x) boron y) krypton z) cesium
Last Answer : ANSWER: X -- BORON
Description : In N-type semiconductors the majority of the carriers are: w) holes x) electrons y) protons z) neutrons
Last Answer : ANSWER: X -- ELECTRONS
Description : Which one of the following particles travels at the speed of light? w) neutrons x) electrons y) photons z) muons
Last Answer : ANSWER: Y -- PHOTONS
Description : Isotopes of an element have different numbers of: w) electrons x) protons y) neutrons z) leptons
Last Answer : ANSWER: Y -- NEUTRONS
Description : When an atomic nucleus emits a beta particle, one of its neutrons disintegrates into one of the following set of particles. Does it disintegrate into: w) a positron and an electron x) a proton, an ... and an antineutrino y) a proton, an electron, and a positron z) a neutrino and an antineutrino
Last Answer : ANSWER: X -- A PROTON, AN ELECTRON AND AN ANTINEUTRINO
Description : Compared to terrestrial environments, aquatic environments are more stable in: w) temperature range x) producer consumer distribution y) sunlight absorbed z) number species
Last Answer : ANSWER: W -- TEMPERATURE RANGE
Description : Pick out the wrong statement. (A) The disintegration rate of a radioactive substance cannot be increased by heating it (B) Electrons have negligible mass and unit negative change (C) Deuterium atom has one proton and two neutrons in its nucleus (D) Cadmium is capable of absorbing neutrons
Last Answer : (C) Deuterium atom has one proton and two neutrons in its nucleus
Description : In radioactive decay, the emission of an electron is characteristic of: w) Alpha decay x) Beta decay y) Gamma decay z) X-rays
Last Answer : ANSWER: X -- BETA DECAY
Description : The emission of a positron from a radioactive atom is generally accompanied by the emission of one of the following. Is it accompanied by the emission of: w) a meson x) a baryon y) an antineutrino z) a neutrino
Last Answer : ANSWER: Z -- A NEUTRINO
Description : In the sun, helium is produced from hydrogen by: w) radioactive decay x) disintegration y) fission z) fusion
Last Answer : ANSWER: Z -- FUSION