When dT = Kf * molality * i
= Kf*m*i
and when molality = (no of moles of solute) / Kg of solvent
= 2.5g /250g x 1 mol /85 g x1000g/kg
=0.1176 molal
and Kf for water = - 1.86 and dT = -0.255
by substitution
0.255 = 1.86* 0.1176 * i
∴ i = 1.166
when the degree of dissociation formula is: when n=2 and i = 1.166
a= i-1/n-1 = (1.166-1)/(2-1) = 0.359 by substitution by a and c(molality) in K formula
∴K = Ca^2/(1-a)
= (0.1176 * 0.359)^2 / (1-0.359)
= 2.8x10^-3
Answer:
Explanation:
3
Explanation:
The reaction expression is given as:
Al(OH)₃ + HNO₃ → H₂O + Al(NO₃)₃
To solve this problem, let us assign coefficient a,b,c and d to each specie;
aAl(OH)₃ + bHNO₃ → cH₂O + dAl(NO₃)₃
Conserving Al : a = d
O: 3a + 3b = c + 9d
H: 3a + b = 2c
N: b = 3d
let a = 1 , d = 1, b = 3 , c = 3
Multiply through by 3;
a = 1, b = 3, c = 3 and d = 1
Al(OH)₃ + 3HNO₃ → 3H₂O + Al(NO₃)₃
Water is called the "universal solvent" because it is capable of dissolving more substances than any other liquid. This is important to every living thing on earth. It means that wherever water goes, either through the air, the ground, or through our bodies, it takes along valuable chemicals, minerals, and nutrients.
Answer:
Number of moles = 0.92 mol
Explanation:
Given data:
Mass of CaSO₄ = 125 g
Number of moles of CaSO₄ = ?
Solution:
Formula:
Number of moles = mass/ molar mass
Molar mass of CaSO₄:
Molar mass of CaSO₄ = 40 + 32+ 16×4
Molar mass of CaSO₄ = 40 + 32+ 64
Molar mass of CaSO₄ = 136 g/mol
Number of moles:
Number of moles = mass/ molar mass
Number of moles = 125 g/ 136 g/mol
Number of moles = 0.92 mol
