Answer:
The boiling point of a 8.5 m solution of Mg3(PO4)2 in water is<u> 394.91 K.</u>
Explanation:
The formula for molal boiling Point elevation is :
= elevation in boiling Point
= Boiling point constant( ebullioscopic constant)
m = molality of the solution
<em>i =</em> Van't Hoff Factor
Van't Hoff Factor = It takes into accounts,The abnormal values of Temperature change due to association and dissociation .
In solution Mg3(PO4)2 dissociates as follow :
Total ions after dissociation in solution :
= 3 ions of Mg + 2 ions of phosphate
Total ions = 5
<em>i =</em> Van't Hoff Factor = 5
m = 8.5 m
= 0.512 °C/m
Insert the values and calculate temperature change:
Boiling point of pure water = 100°C = 273.15 +100 = 373.15 K
= 373.15 K[/tex]
21.76 = T - 373.15
T = 373.15 + 21.76
T =394.91 K
The steam releases 39.9 kJ when it condenses..
The steam condenses and transfers its energy to the skin.
<em>q = m</em>Δ<em>H</em>_cond = 17.7 g × (-2257 J/1 g) = -39 900 kJ = -39.9 kJ
The negative sign shows that the steam is releasing energy
Answer:
because too much can neutralise the results
Answer:
Explanation:
Heat required to convert ice to ice at 0⁰C
= mass x specific heat x rise in temperature
= 18 x 2.09 x 20
= 752.4 J .
heat required to convert ice at 0⁰C to water at 0⁰C
mass x latent heat of fusion
= 18 x 336
= 6048 J
Heat required to increase the temperature of water to 100⁰C
= 18 x 4.2 x 100
= 7560 J
Total heat required
7560 + 6048 + 752.4
= 14360.4 J
