False
Explanation:
Electron affinity is negative when energy is absorbed and it is positive when energy is released.
Electron affinity is defined as the energy released in adding an electron to a neutral atom in the gas phase.
It is a measure of the readiness of an atom to gain an electron.
In a reaction where energy is released, electron affinity is usually positive. These reactions are called exothermic reactions.
Endothermic reactions in which energy is absorbed have negative electron affinity values.
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The decreasing order of wavelengths of the photons emitted or absorbed by the H atom is : b → c → a → d
Rydberg's formula :
,
where λ is the wavelength of the photon emitted or absorbed from an H atom electron transition from
to
and
= 109677 is the Rydberg Constant. Here
and
represents the transitions.
(a)
=2 to
= infinity
= 109677/4 [since 1/infinity = 0] Therefore,
= 4 / 109677 = 0.00003647 m
(b)
=4 to
= 20
= 6580.62
Therefore,
= 1 / 6580.62 = 0.000152 m
(c)
=3 to
= 10
= 11089.56
Therefore,
= 1 / 11089.56 = 0.00009 m
(d)
=2 to
= 1
= - 82257.75
Therefore,
= 1 /82257.75 = - 0.0000121 m
[Even though there is a negative sign, the magnitude is only considered because the sign denotes that energy is emitted.]
So the decreasing order of wavelength of the photon absorbed or emitted is b → c → a → d.
Learn more about the Rydberg's formula athttps://brainly.com/question/14649374
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Answer: There is no list in your question. But the three factors in which natural selection occurs are:
1. A struggle for existence,
2. Variation and
3. Inheritance
Explanation:
Darwin’s theory of natural selection is the way in which organisms change overtime.
These changes allow organisms to become better adapted to their environment and increase their chances for survival.
The three major factors through which natural selection occurs are:
1. A struggle for existence,
2. Variation and
3. Inheritance
Darwin’s theory of natural selection will occur if the three conditions above are met and unless these factors are in place, natural selection will not occur.
Answer:
Mass of heptane = 102g
Vapor pressure of heptane = 454mmHg
Molar mass of heptane = 100.21
No of mole of heptane = mass/molar mass = 102/100.21
No of mole of heptane = 1.0179
Therefore the partial pressure of heptane = no of mole heptane *Vapor pressure of heptane
Partial pressure of heptane = 1.0179*454mmHg
Partial pressure of heptane = 462.1096 = 462mmHg
the partial pressure of heptane vapor above this solution = 462mmHg