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

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
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ANSWER: Y -- HIGH MELTING POINT
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Metals are good conductors of electricity because – (1) they contain free electrons (2) the atoms are lightly packed (3) they have high melting point (4) All of the above

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Which of the following is the same for both radioactive iodine and stable iodine? w) number of neutrons x) mass number y) half-life z) chemical properties

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