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1) Generally sodium chloride is known as a. Poisonous salt b. Table salt c. Chinese salt d. Japanese salt
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2) The symbol of "Fluorine" is a. C b. N c. O d. Fl
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3) A tiny dense nucleus in an atom was discovered by a. Greek scientist b. Roman philosopher c. New Zealand-born physicist d. British mathematician
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4) The smallest particle of water is a. element b. atom c. molecule d. neutron
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5) The atomic number of sodium is 11 and its atomic mass is 23 and the number of protons and neutrons in an atom of sodium is a. 11 and 11 b. 11 and 23 c. 23 and 11 d. 11 and 12
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6) Most of the covalent compounds are found in a. solid state b. gaseous state c. liquid state d. both in liquid and gaseous state
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7) The radioactive isotope of carbon is a. carbon-12 b. carbon-13 c. carbon-14 d. carbon-6
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8) Nuclear batteries are a. small in size b. very heavy c. harmful d. enlarge in size
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9) Isotopes behave the same way in a. chemical reaction b. bonding c. electrical conductivity d. physical reaction
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10) In methane gas, each carbon atom is bonded with a. two oxygen atoms b. two hydrogen atoms c. three oxygen atoms d. four hydrogen atoms
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11) Oxygen is a diatomic gas so its chemical formula is a. O² b. O₂ c. O d. Ox
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12) The atomic number of helium is a. 1 b. 2 c. 3 d. 4
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13) The atomic number of hydrogen is a. 1 b. 2 c. 3 d. 4
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14) Neutrons have a. negative charge b. positive charge c. no charge d. both charges
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15) Strong radioisotopes can be used to destroy a. organs b. bacteria c. viruses d. cancer cells
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16) The ionic chemical formula of aluminum is a. Al-2 b. Al+2 c. Al-3 d. Al+3
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17) When shell K is completed, next electron moves to a. shell M b. shell S c. shell P d. shell L
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18) The atomic number of carbon is 6, hence there are a. 2 protons and 4 electrons b. 6 protons and 12 electrons c. 6 protons and 12 neutrons d. 12 protons and 6 electrons
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19) The first electromagnetic generator "Faraday disk" was built in a. 1381 b. 1831 c. 1813 d. 1183
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20) If no loss or gain of electrons occur by mixing of two atoms, we say that they may be attached to each other due to a. proton attraction b. neutron attraction c. sharing of electrons d. opposite charges
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