Answer is "C".
<em><u>Explanation
</u></em>
Single replacement reaction is a type of reaction which one reactant reacts with another and makes a product by replacing one element by another.
Mg (Magnesium) reacts with Al₂O₃ (Aluminium oxide) and produces MgO (Magnesium oxide) and Al (Aluminium) as products. Here Al is replaced by Mg. Reaction is
Mg + Al₂O₃ → MgO + Al
To balance the reaction equation, both left and right hand sides should have same number of atoms in each element.
Here,
<em>Left Hand Side has </em> <em>Right Hand Side has</em>
Mg = 1 atom Mg = 1 atom
Al = 2 atom Al = 1 atom
O = 3 atom O = 1 atom
First step : balance the O atoms in both sides. To do that "3" should be added before MgO.
Second step : After balancing O atoms, there will be 3 Mg atoms in right hand side. Hence to balance Mg atoms again "3" should be added before Mg in left hand side
Third step : as the final step balance the Al atoms by adding "2" before Al in the right hand side.
Then final balanced equation should be
3Mg + Al₂O₃ → 3MgO + 2Al
Answer:
2.4 × 10⁻⁴ M
Explanation:
Step 1: Calculate the concentration of Mg²⁺ coming from Mg(NO₃)₂
Mg(NO₃)₂ is a strong electrolyte and the molar ratio of Mg(NO₃)₂ to Mg²⁺ is 1:1. The initial molar concentration of Mg²⁺ is 1/1 × 0.36 M = 0.36 M.
Step 2: Make an ICE chart for the solution of MgF₂
MgF₂(s) ⇄ Mg²⁺(aq) + 2 F⁻(aq)
I 0.36 0
C +S +2S
E 0.36+S 2S
The solubility product constant is:
Ksp = [Mg²⁺] × [F⁻]² = (0.36+S) × (2S)²
Since S <<< 0.36, 0.36+S ≈ 0.36.
Ksp = 0.36 × 4S² = 8.4 × 10⁻⁸
S = 2.4 × 10⁻⁴ M
Hi,
The purpose of the burning splint is to provide activation energy.
