Explanation:
Upon dissolution of KCl heat is generated and temperature of the solution raises.
Therefore, heat generated by dissolving 0.25 moles of KCl will be as follows.
= 4.31 kJ
or, = 4310 J (as 1 kJ = 1000 J)
Mass of solution will be the sum of mass of water and mass of KCl.
Mass of Solution = mass of water + (no. of moles of KCl × molar mass)
= 200 g + 
= 200 g + 13.625 g
= 213.625 g
Relation between heat, mass and change in temperature is as follows.
Q = 
where, C = specific heat of water = 
Therefore, putting the given values into the above formula as follows.
Q =
4310 J = 
Thus, we can conclude that rise in temperature will be 
.
the energy gained by proteins and carbohydrates differs from the energy gained by fats.
proteins and carbohydrates both give 4 kcal per gram
fats give 9 kcal per gram
mass of proteins - 2 g
energy given by proteins - 2 g x 4 kcal/g = 8 cal
mass of carbohydrates - 20 g
energy given by carbohydrates - 20 g x 4 kcal/g = 80 cal
mass of fat - 1 g
energy given by fat - 1 g x 9 kcal/g = 9 cal
total energy = 8 + 80 + 9 = 97 kcal
energy = 97 kcal
Answer:
Molarity = 0.24 M
Explanation:
Given data:
Number of moles of Mg(NO₃)₂ = 0.181 mol
Volume of solution = 0.750 L
Molarity of solution = ?
Solution:
Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.
Formula:
Molarity = number of moles of solute / L of solution
by putting values,
Molarity = 0.181 mol / 0.750 L
Molarity = 0.24 M
Answer:
¨molecular compounds are formed by the sharing of electrons, and ionic compounds are formed by the transfer of electrons¨
Explanation:
