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______ are elements that are shiny and good conductors of heat and electricity.
We can describe a substance or a metal by its __________.
Steel, iron, nickel and cobolt are the only ________ metals.
A _____ object reflect light well.
Metals are good __________ of heat and electricity.
Materials which do not let energy flow though them easily are called __________.
A ________ is a substance that has two or more elements in it.
A ________ is a group of atoms joined together.
We can show the number of atoms in a molecule by using the chemical _______.
If we use the materials again instead of throwing them away, our use of them becomes more ___________.
A _________ energy resource is one that can be replaced.
