I think the first question is talking about the ionic compound Sodium sulfide and it’s formula is Na2S.
And for the second question, i’m pretty sure it’d be a positive charge
Answer:
6.0 ×
W/
Explanation:
From Wien's displacement formula;
Q = e A
Where: Q is the quantity of heat transferred, e is the emissivity of the surface, A is the area, and T is the temperature.
The emissive intensity =
= e
Given from the question that: e = 0.6 and T = 1000K, thus;
emissive intensity = 0.6 × 
= 0.6 × 1.0 × 
= 6.0 ×

Therefore, the emissive intensity coming out of the surface is 6.0 ×
W/
.
The answer is 107 degrees. The geometric shape for ammonia is Trigonal Pyramidal, even though its electron geometry is “Tetrahedral”. This is because ammonia has a lone pair of electrons that occupy its space like the other 3 hydrogens in the geometric structure.
The answer 180 degrees. This is because of the linear geometric structure of carbon dioxide. The oxygen atom is on either side of the carbon atom, each is bound by a double covalent bond. All the atoms are involved in the bond and there are no one pair electrons.
The answer is tetrahedral geometry. This is because all the 4 valence electrons of the carbon are involved in a bond with a hydrogen atom. The angles in a tetrahedral geometric arrangement, such as in methane, is 109.5 degrees, where the hydrogen atoms are as far apart, from each other, as possible .
The best and most correct answer among the choices provided by the question is the fourth choice. The phenomenon that Michael Faraday explored was electricity and magnetism. I hope my answer has come to your help. God bless and have a nice day ahead!
It is because gravity is pushing down on the ball