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3 years ago

7

Se tienen 500g de alcohol etílico a una temperatura de -40 °C ¿Cuánto calor se necesita para transformarlo a vapor a una tempera

tura de 150ºC?

1 answer:

Feliz [49]3 years ago

8 0

The question is: You have 500g of ethyl alcohol at a temperature of -40 ° C. How much heat is needed to transform it into steam at a temperature of 150ºC?

Answer: 233700 J heat is needed to transform ethyl alcohol into steam at a temperature of $-40^{o}C$ to $150^{o}C$ .

Explanation:

Given: Mass = 500 g

Initial temperature = $-40^{o}C$

Final temperature = $150^{o}C$

The standard value of specific heat of ethyl alcohol is $2.46 J/g ^{o}C$ .

Formula used to calculate the heat energy is as follows.

$q = m \times C \times (T_{2} - T_{1})$

where,

q = heat energy

m = mass of substance

C = specific heat

$T_{1}$ = initial temperature

$T_{2}$ = final temperature

Substitute the values into above formula as follows.

$q = m \times C \times (T_{2} - T_{1})\\= 500 g \times 2.46 J/g^{o}C \times [150 - (-40)]^{o}C\\= 233700 J$

Thus, we can conclude that 233700 J heat is needed to transform ethyl alcohol into steam at a temperature of $-40^{o}C$ to $150^{o}C$ .

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Answer:

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$\frac{F_{gf}}{F_{g0}}=2$

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