Oxygen and neon are both elements. Oxygen has 8 electrons and 8 protons. Neon has 10 electrons and 10 protons. Oxygen is also a non-metal element and Neon is a noble gas.
He has to use a different colored light at a higher frequency.
SAMPLE A - <span>pure substance.
</span>SAMPLE B - <span>homogeneous mixture.
</span>SAMPLE C - <span>heterogeneous mixture.
</span>Pure substance - <span>constant composition and properties.</span>
Homogeneous mixture - same uniform appearance and composition.
Heterogeneous mixture - <span>not </span>uniform<span> in composition, two phases (liquid and dust).
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