GCE AS Physics (Thermal Physics)
[From: ] [author: ] [Date: 11-05-03] [Hit: ]
Q2 It is true.Chlorine and hydrogen molecules have the same average kinetic energy at the same temperature.But the average speed of chlorine molecules is much less - to compensate for the larger mass of the chlorine molecules.Q3(B) Work out the resistance at 0degC (273K) and at 100degC (373K).These 2 temperatures are the reference points for an empirical scale.Then work out the temperature which gives R=15.......
(C)the ratio of pressures exerted on the walls of the container"
This question CAN be answer using the concepts, but i need the answer for it in calculations.
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I appreciate all help as SOON as possible, and any sort of help is really appreciated.
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Q1 No. You must have T in kelvin (abs temp). For example, if it were possible, for some value of R PV would always be zero at zero centigrade, which is clearly not possible.
Q2 It is true. Chlorine and hydrogen molecules have the same average kinetic energy at the same temperature. But the average speed of chlorine molecules is much less - to compensate for the larger mass of the chlorine molecules.
Q3(B) Work out the resistance at 0degC (273K) and at 100degC (373K). These 2 temperatures are the reference points for an empirical scale. Then work out the temperature which gives R=15.8ohm (assuming you have worked out 15.8ohms correctly!) by proportion (from the reference point values - NOT the equation)
Q4A Since the mass of an oxygen molecule is 16 times the mass of a hydrogen molecule, and we have equal masses of each, there will be a lot more hydrogen molecules:
(No of H):(No of O) = 16:1
Q4B. 1:1 - see answer to Q2
Q4C Use PV=nRT (V, T and R are the same for both gases). n is 16 times bigger for H than O (16 times more particles) therefore
(Press of H):(Press of O) = 16:1
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mass of 1 oxygen molecule = m_O
mass of 1 hydrogen molecule = m_H
m_O = 16m_H
No. of oxygen molecules = N_O
No. of hydrogen molecules = N_H
Mass of oxygen = N_O x m_O
Mass of hydrogen = N_H x m_H
We have equal masses of each gas, so
N_H x m_H = N_O x m_O
N_H / N_0 = m_O / m_H = (16m_H) / m_H = 16
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mass of 1 oxygen molecule = m_O
mass of 1 hydrogen molecule = m_H
m_O = 16m_H
No. of oxygen molecules = N_O
No. of hydrogen molecules = N_H
Mass of oxygen = N_O x m_O
Mass of hydrogen = N_H x m_H
We have equal masses of each gas, so
N_H x m_H = N_O x m_O
N_H / N_0 = m_O / m_H = (16m_H) / m_H = 16
Report Abuse
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mass of 1 oxygen molecule = m_O
mass of 1 hydrogen molecule = m_H
m_O = 16m_H
No. of oxygen molecules = N_O
No. of hydrogen molecules = N_H
Mass of oxygen = N_O x m_O
Mass of hydrogen = N_H x m_H
We have equal masses of each gas, so
N_H x m_H = N_O x m_O
N_H / N_0 = m_O / m_H = (16m_H) / m_H = 16
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