54. fluorine
55. oxygen
56. they have the same number of protons
57. nucleus 3
Explanation:
54. The element represented by the nucleus 1 have 9 protons and 9 neutrons. The atomic number of the element is equal to the number of protons = 9, so the element is fluorine.
55. The element represented by the nucleus 2 have 8 protons and 10 neutrons. The atomic number of the element is equal to the number of protons = 8, so the element is oxygen.
56. nucleus 2 contains 8 protons and 10 neutrons
nucleus 4 contains 8 protons and 11 neutrons.
The atoms that have the same number of protons but different number of neutrons are called isotopes.
57. nucleus 3 have 10 protons and 10 neutrons and correspond to neon. Neon have 10 electrons (equal to the number of protons) and have the electronic configuration 1s² 2s² 2p⁸. Because all the electrons shells are filled with electrons, neon have a stable electron configuration.
Learn more about:
subatomic particles
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The answer would be A: its container.
Gas will expand to fill whatever container it is put in.
Correct answer: "A. Energy from an outside source is continuously being added."
An endothermic reaction is a reaction that is characterised by the system absorbing energy from its surroundings. That energy is usually in heat form. For example, when mixing water<span> with potassium chloride, this reaction will absorb heat and the container will feel cold - endothermic reaction.</span>
Here you go! There are 0.9307 moles in 123.0 g of the compound. I solved this by using a fence post method. I calculated the number of grams in one mol of (NH4)2 SO4 and got 132.16.
I did this by finding the atomic mass of each element on the periodic table (my work is in the color blue for this step)
After that, i divided the given mass by the mass of one mol of the compound.
The answer is 0.9307 moles!! I hope this helped you! :))
I picture is unclear but
I can help if u send me it