September 28, 2020, 06:22:12 PM
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#### greenfuzzpickles

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« on: September 15, 2020, 06:39:05 PM »
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.
« Last Edit: September 15, 2020, 07:36:22 PM by greenfuzzpickles »

#### Babcock_Hall

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« Reply #1 on: September 15, 2020, 07:12:44 PM »

#### greenfuzzpickles

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« Reply #2 on: September 15, 2020, 07:40:01 PM »
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

#### Borek

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« Reply #3 on: September 16, 2020, 03:06:14 AM »
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.
« Last Edit: September 16, 2020, 04:25:43 AM by Borek »
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#### AWK

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