Answer:
The correct answer is there is a mistake in the calculation. The second law of thermodynamics state that in any spontaneous process there is an increase in the entropy of the universe.
Explanation:
According to the second law a reaction will occur in a system spontaneously if the total entropy of both system and surrounding increases during the reaction.That means in case of spontaneous reaction entropy change is always positive.
But according to the question the reaction H2+F2=2HF is spontaneous in all temperature.So according to the second law of thermodynamics i can say that my classmate made a mistake in calculation that"s why his result for entropy change comes negative.
Mass is the answer to your question . thanks ;)
surrounds the nucleus of an atom in various energy levels called orbitals.
Explanation:
Electrons surrounds the nucleus of an atom in various energy levels called orbitals.
According to the Bohr's model of an atom, the extra nuclear space is made up of electrons in specific spherical orbits called shells or energy levels.
- The region of a maximum probability of where an electron is located is sometimes referred to as an electron cloud or orbital.
- Electrons move round the nucleus in certain permissible orbits.
- An electron in an energy level posses a definite amount of energy associated with it at that level.
- Electrons moves through the energy levels by gaining or losing energy.
Learn more:
Bohr brainly.com/question/4986277
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