Aluminum sulfide : Al₂S₃
ratio cation : anion = 2 : 3
<h3>Further explanation</h3>
Given
Compound of Aluminium
Required
cations anions ratio
Solution
Salt can be formed from cations and anions which have their respective charges.
In the chemical compound formula these charges are crossed with each other
For aluminum it has a +3 charge
1. Aluminum carbide : Al₄C₃
ratio cation : anion = 4 : 3
2. Aluminum chloride : AlCl₃
ratio cation : anion = 1 : 3
3. Aluminum sulfide : Al₂S₃
ratio cation : anion = 2 : 3
4. Aluminum nitride : AlN
ratio cation : anion = 1 : 1
The reaction equation is:
CaF₂ + H₂SO₄ → 2HF + CaSO₄
The molar ratio between fluorite and hydrogen fluoride is 1 : 1.
The moles of fluorite supplied are:
Moles = 15.6 / 78.07
Moles = 0.200
The moles of hydrogen fluoride produced will be 0.2.
Now, we may use the ideal gas equation to determine the temperature:
PV = nRT
T = PV/nR
T = (899 * 7.4) / (0.2 * 62.36)
T = 533.40 K
The temperature will be 260.25 °C
Answer:
The correct option is a.
Explanation:

125 kPa
125kpa - 2x 4x x
Total pressure after reaction = 176 kPa
125 kPa - 2x + 4x + x = 176 kPa
x = 17
125 kpa - 2x = 125 kPa - 2(17) = 91 kPa
Initial pressure of the dinitrogen pentoxide ,(at t=0) =
Final pressure of the dinitrogen pentoxide, (at t = t) = P = 91 kPa
The rate constant is = 



It will take 113 minutes for the total pressure to reach 176 kPa.