Answer:
130 g of sucrose
Explanation:
Boiling point elevation formula → ΔT = Kb . m
ΔT = Boiling T° solution - Boiling T° pure solvent → 0.39°C
0.39°C = 0.513°C/m . M
m = 0.760 mol/kg → molality = moles of solute / 1kg of solvent
Let's determine the moles of solute → molality . kg
0.760 mol/kg. 0.5 kg = 0.380 moles
If we convert the moles to mass, we'll get the answer
0.380 mol . 342.30 g/mol = 130g
Answer:
53 Joules
Explanation:
Applying the law of conservation of mechanical energy.
Law of conservation of mechanical energy: States that energy although, energy can not be transformed from one form to another, the total energy of the system remain the same.
I.e,
Mechanical Energy = E.K+P.E..................... Equation 1
Where E.K = Kinetic energy, P.E = Potential energy.
From the question,
Given: Mechanical energy = 65 Joules, K.E = 12 J
Substitute these values into equation 1 and solve for P.E
65 = 12+P.E
P.E = 65-12
P.E = 53 Joules
Answer:
Below
Nitric acid
Lead
Sodium nitrate
Explanation:
The activity series is an arrangement of metals in order of decreasing reactivity. Metals that are higher up in the series displace metals that are lower in the series from dilute solutions. Hence, when the ion of a metal that is lower in the series reacts with a metal that is higher up in the series, the latter is oxidized.
Dilute acids dissolve metals above hydrogen in the activity series such as as zinc and lead. Platinum is much lower than sodium in the activity series hence platinum does not react with sodium nitrate.
This in turn determines whether the substance exists in the solid, liquid, or gaseous state. Molecules in the solid phase have the least amount of energy, while gas particles have the greatest amount of energy. The temperature of a substance is a measure of the average kinetic energy of the particles.
% m/v of the solution = 0.2%m/v
<h3>Further explanation</h3>
or
% m/v = g solute / 100 ml solution
Concentration : 2 g sodium borate / L water
For 10 L⇒20 g Sodium borate