Moles of ammonium sulfide = 5.80 mol
The formula of ammonium sulfide is (NH₄)₂S
So each molecule of ammonium sulfide has (4 x 2) or 8 atoms of H
One mole of ammonium sulfide has 8 moles of H
5.80 mol of ammonium sulfide has (8 x 5.8) or 46.4 moles of H
As per the definition of Avogadro's number, 1 mole = 6.022 x 10²³ atoms
46.4 moles of H x (6.022 x 10²³ atoms/ 1 mole of H)
= 2.8 x 10²⁵ H atoms
Therefore, 2.8 x 10²⁵ H atoms are in 5.80 mol of ammonium sulfide.
<h3>
Answer: Si (choice D)</h3>
This is the element Silicon.
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Explanation:
First convert each percentage to its decimal form.
For example, 92.2297% converts to 0.922297 after moving the decimal point two spots to the left.
After doing that, multiply those decimal values with their respective atomic mass unit (amu) values.
- 27.9769 * 0.922297 = 25.8030109393
- 28.9765 * 0.046832 = 1.357027448
- 29.9738 * 0.030872 = 0.9253511536
Then we add up the results
25.8030109393 + 1.357027448 + 0.9253511536 = 28.0853895409
That rounds to about 28.085
Then look at the periodic table to see the atomic mass of Cobalt (Co), Aluminum (Al), Nickel (Ni) and Silicon (Si). The mass values listed in the periodic table are weighted averages of all the isotopes. The units for the mass are still in amu.
- Cobalt = 58.933
- Aluminum = 26.982
- Nickel = 58.693
- Silicon = 28.085
We have a match with silicon, showing that <u>choice D</u> is the final answer.
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There seem to be 3 major discoveries about particles that year. The first is neutrino oscillation is </span>demonstrated. Next, supernovae observations suggest that the expansion of the universe is accelerating. Time reversal asymmetry is observed for K meson decay
Sulfur has 6 electrons, so we put 6 in the first spot.
Oxygen has 6 electrons too, but since there are 3, we would multiply 6 times 3 , which equals 18, then add that too.
The 2 is added because there is that negative 2 at the top of the formular, which indicates the presence of two extra valence electrons.
the equation would be
6 + 18 + 2 = 26
B, C, F, and G are all elements
How did I determine that answer? I looked at a periodic table.
Tin - Sn
Chromium - Cr
Arsenic - As
Nickel - Ni
Bronze is a copper alloy, not an element.
Solder is an alloy made of led or tin (sometimes brass or silver)
Propane is Alkane made up of Carbon and Hydrogen