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2 years ago

If an endothermic process absorbs 256j how many kilocalories are absorbed

2 answers:

8 0

There are several units for expressing energy, Most common are joules and kilocalories.

The conversion factor of joule to kilocalories is
1 kilo calorie = 4184 J
∴ x kilo calorie = 256 J

x = $\frac{256}{4184} = 0.0611$ kilo calories

Thus, 256 J = 0.0611 kilocalories

astra-53 [7]2 years ago

5 0

Answer: 0.0612 kcalories

Explanation:

Endothermic processes are those processes in which heat is absorbed and exothermic processes are those processes in which heat is released.

Standard units for heat measurement are Joules and calories wherein

1 joule = 0.239 calorie.

As 1 Joule is equivalent to 0.239 calorie

256 Joules are equivalent to= $\frac{0.239}{1}\times 256=61.2calories$

Now 1 cal = 0.001 kcalories

Therefore 61.2 calories= $\frac{0.001}{1}\times 61.2=0.0612kcal$

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2 years ago

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The maximum height at which nitrogen molecule will go before coming to rest is 14 kilometers.

Given:

The nitrogen gas molecule with a temperature of 330 Kelvins is released from Earth's surface to travel upward.

To find:

The maximum height of a nitrogen molecule when released from the Earth's surface before coming to rest.

Solution:

The maximum height attained by nitrogen gas molecule = h
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The average kinetic energy of the gas particles is given by:

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Mass of nitrogen gas molecule = m

$m= \frac{ 28.0134 g/mol}{6.022\times 10^{23} mol^{-1}}=4.652\times 10^{-23} g\\\\1g=0.001kg\\\\m=4.652\times 10^{-23}\times 0.001 kg\\\\=4.652\times 10^{-26} kg$

The acceleration due to gravity = g = 9.8 m/s^2
The maximum height attained by nitrogen gas molecule = h
The potential energy is given by:

$P.E=mgh$

$6.381\times 10^{-21} J=4.652\times 10^{-26} kg\times 9.8 m/s^2\times h\\\\h=\frac{6.381\times 10^{-21} J}{4.652\times 10^{-26} kg\times 9.8 m/s^2}\\\\h=13,996.6 m\\\\1 m = 0.001 km\\\\h=13,996.6 m=h=13,996.6\times 0.001 k m\\\\=13.9966 km \approx 14 km$

The maximum height at which nitrogen molecule will go before coming to rest is 14 kilometers.

Learn more about the average kinetic energy of gas particles here:

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