Answer:
0.297 °C
Step-by-step explanation:
The formula for the <em>freezing point depression </em>ΔT_f is
ΔT_f = iK_f·b
i is the van’t Hoff factor: the number of moles of particles you get from a solute.
For glucose,
glucose(s) ⟶ glucose(aq)
1 mole glucose ⟶ 1 mol particles i = 1
Data:
Mass of glucose = 10.20 g
Mass of water = 355 g
ΔT_f = 1.86 °C·kg·mol⁻¹
Calculations:
(a) <em>Moles of glucose
</em>
n = 10.20 g × (1 mol/180.16 g)
= 0.056 62 mol
(b) <em>Kilograms of water
</em>
m = 355 g × (1 kg/1000 g)
= 0.355 kg
(c) <em>Molal concentration
</em>
b = moles of solute/kilograms of solvent
= 0.056 62 mol/0.355 kg
= 0.1595 mol·kg⁻¹
(d) <em>Freezing point depression
</em>
ΔT_f = 1 × 1.86 × 0.1595
= 0.297 °C
A balanced equation is a prime example of the law of the conservation of mass as the number of atoms in the reactants is consistent with the number of atoms in the reactants meaning the amount of matter has not changed and no mass has been created or destroyed hence obeying the law.
The motion of particles can be changed by the temperature you put it at.
Answer:
The correct answer is in an exothermic reaction the energy of the product is less than the energy of the reactants.
Explanation:
Exothermic reaction is a type of reaction that generates heat.As a result in case of an exothermic reaction the energy of the reactant is more than the energy of the product.
That"s why the enthalpy change in an exothermic reaction is always positive .
Answer:
It was not until he was 50 years old, in 1859.
Explanation:
