You may have noticed an error in your results. If you measured a rectangular ingot, the corners are rounded. On both coins and ingots, the edges are thicker than the rest of the object. Explain how these errors will affect your calculated density compared to the actual density.

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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.