The answer is B. light is reflected off the shirt
Answer: C) Either benzene or oxygen may limit the amount of product that can be formed
Explanation: Benzene and oxygen are the reactants of the equation. What type and the amount of reactants there are in a chemical reaction affects the outcome. Therefore, seeing as benzene and oxygen are the reactants, the answer is C).
Answer: 
Explanation:Bond energy of H-H is 436.4 kJ/mole
Bond energy of C-H is 414 kJ/mol
Bond energy of C=C is 620 kJ/mol
Bond energy of C≡C is 835 kJ/mol

= {1B.E(C≡C)+2B.E(C-H) +1B.E(H-H)} - {1B.E(C=C)+4B.E(C-H)}


4X + 3O₂ = 2X₂O₃
n(X₂O₃)=0.02225 mol
m(X)=4.000 g
x - the molar mass of metal
m(X)/4x=n(X₂O₃)/2
x=m(X)/{2n(X₂O₃)}
x=4.000/{2*0.02225)=89.89 g/mol
X=Y (yttrium)