What is the enthalpy change when 49.4 ml of 0.430 m sulfuric acid reacts with 23.3 ml of 0.309 m potassium hydroxide?
1 answer:
You might be interested in
Answer:
215.12 g
Explanation:
The change in the bolling temperature is a collateral property called ebullioscopy. The elevation on temperature occurs because there'll be a solute in the pure compound, and that solute(generally non-volatile) has a different boiling point, so the total bolling pint should increase.
To calculate the elevation in the temperature, we must use the Raoult equation:
ΔT = KbxWxi
Where <em>ΔT</em> is the variation of the temperature of boiling point, <em>Kb</em> is the
ebullioscopy constant, <em>W</em> is the molarity, and <em>i</em> the Vant' Hoff factor, which for molecules is also equal to 1, because they don't form ions. So:
82.00 - 78.40 = 1.22xW
W = 3.60/1.22
W = 2.9508
The molarity can also be calculated by:
Where <em>m1</em> is the mass of the solute (in grames), <em>M1</em> is the molar mass of the solute, and <em>m2</em> is the mass of the solvent (in kg).
The density of ethanol is 0.789 g/cm³, and 1 mL = 1 cm³, so 600.00 mL = 600.00 cm³ :
0.789 = m2/600
m2 = 473.4 g = 0.4734 kg
The molar mass of geraniol is:
C: 12 g/mol x 10 = 120 g/mol
H: 1 g/mol x 18 = 18 g/mol
O: 16 g/mol x 1 = 16 g/mol
M1 = 154 g/mol
Then:
m1 = 215.12 g of geraniol.