Planets near the Sun are composed of mainly rock and iron. How does the Solar Nebula theory account for this?

The Solar Nebula Theory accounts for the creation of solar systems, stars, and planets. The theory accounts for planet composition by stating that iron compounds, silicates, and dust clump together to form planetesimals. Because of the proximity of the sun, ices and gases cannot condensate near them, so they do not become gas giants. The planetesimals then collide together due to gravity and collect to form our rocky planets.

Explanation:

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

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since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.