Answer:
28
Explanation:
it states that the atom is neutral, meaning the number of electrons and protons are the same. so if there are 13 electrons, there are 13 protons. And the mass number is neutrons plus protons. So 13+15 is 28
Answer is: energy is absorbed.
According to the Bohr model of the atom:
1. Electrons orbit the nucleus in orbits that have a set size and energy.
2. Energy levels of electrons are discrete (certain discrete values of energy).
3. Electrons can jump from one energy level to another, absorbing or emitting electromagnetic radiation with a frequency ν (energy difference of the levels).
Answer:
detail is given below.
Explanation:
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
For example:
In given photosynthesis reaction:
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
The given equation is balanced chemical equation of photosynthesis. There are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass.
If equation is not balanced,
CO₂ + H₂O → C₆H₁₂O₆ + O₂
It can not follow the law of conservation of mass because mass is not equal on both side of equation.
Answer:
C. cooler than both the crust and the core
Explanation:
It is observed that at the mantle, temperatures range from estimatedly 200 °C (392 °F) around the upper boundary with the crust to approximately 4,000 °C (7,230 °F) at the core-mantle boundary.
So we can say the mantle is cooler than both the crust and the core.
<span>1.0 x 10-14. That is the value of Kw at 25 degrees C.
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