Answer:
Option D. Al is above H on the activity series.
Explanation:
The equation for the reaction is given below:
2Al + 6HBr —> 2AlBr₃ + 3H₂
The activity series gives us a background understanding of the reactivity of elements i.e how elements displace other elements when present in solution.
From the activity series of metals, we understood that metal higher in the series will displace those lower in the series.
Considering the equation given above, Al is higher than H in the activity series. Thus, the reaction will proceed as illustrated by the equation.
Therefore, we can conclude that the reaction will only occur if Al is higher than H in the activity series.
Answer : The value of 
for the reaction is, -565.6 kJ
Explanation :
First we have to calculate the molar mass of CO.
Molar mass CO = Atomic mass of C + Atomic mass of O = 12 + 16 = 28 g/mole
Now we have to calculate the moles of CO.
Now we have to calculate the value of for the reaction.
The balanced equation will be,
From the balanced chemical reaction we conclude that,
As, 
of CO release heat = 10.1 kJ
So, 2 mole of CO release heat = 
Therefore, the value of for the reaction is, -565.6 kJ (The negative sign indicates the amount of energy is released)
According to law of definite proportion, for a compound, elements always combine in fixed ratio by mass.
The formula of compound remains the same, let it be a_{x}b_{y} where, a and b are two different elements.
Since, the ratio of mass remains the same , calculate the ratio of masses of element a and b in both cases
\frac{a}{b}=\frac{15}{35}=\frac{10}{y}
rearranging,
y=\frac{10\times 35}{15}=23.3
Thus, mass of b produced will be 23.3 g.
So your answer would pretty much be 2.80 x 10^24. The picture is just the explanation and how you would get that answer.
Chemists have developed insulation.
