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.
Lower
Melting points of molecular solids are lower than melting points of ionic compounds
Answer:

Explanation:
To solve this problem, we can use the Combined Gas Laws:

Data:
p₁ = 1.7 kPa; V₁ = 7.5 m³; T₁ = -10 °C
p₂ = ?; V₂ = 3.8 m³; T₂ = 200 K
Calculations:
(a) Convert temperature to kelvins
T₁ = (-10 + 273.15) K = 263.15 K
(b) Calculate the pressure

I’m positive it’s gonna be c