Answer:
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Explanation:
It depends on the type of reactants carrying out the reaction.
Matter is anything that has mass and occupies space, It can exist in 3 states, or phases: solid, liquid, and gas.
Solid molecules are closely packed together and retain a fixed shape.
Liquid molecules aren't packed very closely, and take the shape of the bottom of the container.
Gas molecules are far apart and fill the container
completely.
Answer: D. 19.9 g hydrogen remains.
Explanation:
To calculate the moles, we use the equation:
a) moles of 
b) moles of 
According to stoichiometry :
1 mole of require 1 mole of
Thus 0.0787 moles of 
require=
of
Thus is the limiting reagent as it limits the formation of product and acts as the excess reagent. (10.0-0.0787)= 9.92 moles of are left unreacted.
Mass of 
Thus 19.9 g of remains unreacted.
