<span>To solve this we need to balance the equations first.
So Hg + S --> HgS is balanced
One mole of Hg requires one mole of S to form one mole of HgS.
Number of moles of Sulphur = mass/ molar mass = 157/32 = 4.906
So 4.90 moles of S reacts with 4.90 moles of Hg.
Hence there are 4.90 moles of 4.90 of Hg.
Mass = number of moles * molar mass of Hg
Mass = 4.906 * 200.59 = 982.891g</span>
Answer:Artificial light from cities has created a permanent "skyglow" at night, obscuring our view of the stars. Here's their map of artificial sky brightness in North America, represented as a ratio of "natural" nighttime sky brightness. In the black areas, the natural night sky is still (mostly) visible.
Explanation:
The number of C atoms in 0.524 moles of C is 3.15 atoms.
The number of 
molecules in 9.87 moles is 59.43 molecules.
The moles of Fe in 1.40 x 
atoms of Fe is 0.23 x 
The moles of 
in 2.30x
molecules of is 3.81.
<h3>What are moles?</h3>
A mole is defined as 6.02214076 × 
of some chemical unit, be it atoms, molecules, ions, or others. The mole is a convenient unit to use because of the great number of atoms, molecules, or others in any substance.
A. The number of C atoms in 0.524 mole of C:
6.02214076 × x 0.524 mole
3.155601758 atoms =3.155 atoms
B. The number of molecules in 9.87 moles of :
6.02214076 × x 9.87
59.4385293 molecules= 59.43 molecules
C. The moles of Fe in 1.40 x atoms of Fe:
1.40 x ÷ 6.02214076 ×
0.2324754694 x moles.
0.23 x moles.
D. The moles of in 2.30x molecules of :
2.30x ÷ 6.02214076 ×
3.819239854 moles=3.81 moles
Learn more about moles here:
brainly.com/question/8455949
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Electronic Configuration of elements in a period is same because If you see the electronic Configuration of elements in a period you will notice that the valence shell electrons for all elements are present in the same Shell. For example, in first period consisting of Hydrogen and Helium, both the elements' valence electrons are present in the same Shell.
Electronic Configuration of Hydrogen,
1s^1
Electronic Configuration of Helium,
1s^2
Both elements' valance electrons are present in the 1st shell
(This is just a small example to understand the concept because other periods are long but the first period is short that's why I gave the example of the first period)
