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Question
Estimate the average thermal energy of a helium atom at the temperature on the surface of the Sun (6000 K).
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Solution
On the surface of the sun, T = 6000 K
Average thermal energy = `3/2` kT
`= 3/2 xx 1.38 xx 10^(-38) xx 6000`
`= 1.241 xx 10^(-19)` J
Hence, the average thermal energy of a helium atom on the surface of the sun is 1.241 × 10–19 J.
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Choose the correct answer:
The graph of PV vs P for gas is
Match the following:
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|
Column A |
Column B |
|
(a) |
cm3 |
(i) Pressure |
|
(b) |
Kelvin |
(ii) Temperature |
|
(c) |
Torr |
(iii) Volume |
|
(d) |
Boyle's law |
(iv) `"V"/"T" = ("V"_1)/("T"_1)` |
|
(a) |
Charles's law |
(v) `"PV"/"T" = ("P"_1 "V"_1)/"T"_1` |
|
|
|
(vi) PV = P1V1 |
Fill in the blanks:
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 (a) |
 (b) |
 (c) |
 (d) |
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