Answer:When a substance undergoes a chemical change some of the chemical changes can be reversed with a chemical change.
Explanation:
A chemical change changes all of the element but some chemical changes but very few can be changed back to its original substance only with a chemical change.
The correct answer for the question that is being presented above is this one: "<span>0.3."
Here it is how to solve.
M</span><span>olecular mass of Ar = 40
</span><span>Molecular mass of Ne = 20
</span><span>Number of moles of Ar = 9.59/40 = 0.239
</span><span>Number of moles of Ne = 11.12/20= 0.556
</span><span>Mole fraction of argon = 0.239/ ( 0.239 + 0.556) = 0.3</span><span>
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<span>An atom is composed of at least three types of subatomic particles. An electron has properties of both waves and particles. An atom is mostly empty space with a dense, positively charged nucleus.</span>
