Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: greenfuzzpickles on September 15, 2020, 06:39:05 PM
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I can't teach myself online and that is all this class has been. I have no idea what to do here for this chart I attached. Can someone help please. I am so lost.
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It remains a forum rule (see red link above) that you must show your attempt or provide your thoughts before we can help you.
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The 2nd picture is what I have, but I'm not entirely sure I understand it. So from what I understand: The atomic number is the same as the number of protons and since all atoms are neutral the number of protons is equal to the number of electrons. The atomic number tells you what number the element is then we calculate the atomic mass by adding the protons and the neutrons multiplying it by 1 amu. So the superscript is the atomic mass and the subscript is the number of protons/electrons
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Apart from one minor mistake for hydrogen it looks OK to me.
Note, that
we calculate the atomic mass by adding the protons and the neutrons multiplying it by 1 amu
is not entirely true. What you get adding number of protons and neutrons is the atomic mass number (AKA nucleon number or mass number). It tells you how many nucleons are in the nucleon, but the mass of the nucleus is a bit lower than the sum of the masses of nucleons (so called mass deficit). As most elements in the nature are mixtures of isotopes atomic mass is a bit different, and is a weighted average of all isotopes present.
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The mass number and atomic number are written to the left of the element's symbol in superscript and subscript respectively.