1) The symbol of copper is..... a) C b) Co c) Cu d) Ca 2) Pb is the symbol of..... a) Phosphorus b) Lead c) Bromine d) Potassium 3) The mass of the atom is concentrated in the .... a) nucleus b) protons c) neutrons d) electrons 4) The atomic number of an element having 6 protons in its nucleus is.... a) 11 b) 12 c) 23 d) 6 5) The mass number of an atom having13electrons and14 neutrons equals a) 13 b) 14 c) 1 d) 27

Science prep1

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