For an aqueous solution of MgBr2, a freezing point depression occurs due to the rules of colligative properties. Since MgBr2 is an ionic compound, it acts a strong electrolyte; thus, dissociating completely in an aqueous solution. For the equation:
ΔTf<span> = (K</span>f)(<span>m)(i)
</span>where:
ΔTf = change in freezing point = (Ti - Tf)
Ti = freezing point of pure water = 0 celsius
Tf = freezing point of water with solute = ?
Kf = freezing point depression constant = 1.86 celsius-kg/mole (for water)
m = molality of solution (mol solute/kg solvent) = ?
i = ions in solution = 3
Computing for molality:
Molar mass of MgBr2 = 184.113 g/mol
m = 10.5g MgBr2 / 184.113/ 0.2 kg water = 0.285 mol/kg
For the problem,
ΔTf = (Kf)(m)(i) = 1.86(0.285)(3) = 1.59 = Ti - Tf = 0 - Tf
Tf = -1.59 celsius
<span>J.j thomson a british physicist was the first to identify the electron in 1987</span>
<span>A Homogeneous Catalyst exists in the same physical state as that of the reaction it catalyzes.
Explanation:
Catalysts are classifies as follow,
1. Homogeneous Catalyst
2. Heterogeneous Catalyst
</span>Homogeneous Catalyst are those which are in same phase as that of reactants are.
Example:
Acetic Acid + Ethanol + H₂SO₄ → Ethyl Acetate + H₂O + H₂SO₄
In this reaction catalyst and reactants all are in same phase i.e. Liquids.
Heterogeneous Catalyst are those which are in different phase as that of reactants are.
Example:
Ethene + H₂ + Ni → Ethane + Ni
In this reaction ethene and hydrogen are gases while Nickle catalyst is in solid state.