Answer: 72 grams of 
are needed to completely burn 19.7 g 
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to molecular mass and contains avogadro's number 
of particles.
To calculate the number of moles, we use the equation:
Putting in the values we get:
According to stoichiometry:
1 mole of 
requires 5 moles of oxygen
0.45 moles of require= 
moles of oxygen
Mass of 
72 grams of are needed to completely burn 19.7 g
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<em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em>
The equilibrium means that amount that are coming equals the amount that are going.
So the correct answers are
<span>2. A person's income and expenses are equal every month.
</span><span>3. The pressure exerted on the inside of a balloon by the gas inside is equal to the pressure exerted on the outside of the balloon by the atmosphere.</span>
Answer:
Green light has longer wavelengths than orange light. Green light has fewer particles than orange light. Green light refracts less than orange light. That is why Green light slows down more quickly than orange light does.
