Answer: The empirical formula of the metal sulfide is
.
Explanation:
Given: Mass of metal = 20.38 g
Mass of metal sulfide = 31.47 g
Moles is the mass of a substance divided by its molar mass.
So, moles of cobalt (molar mass = 59 g/mol) are as follows.

Moles of bromine (molar mass = 80 g/mol) are as follows.

Now, the ratio of number of moles of cobalt and number of moles of bromine are as follows.
Moles of Co : Moles of Br = 1 : 2
Hence, the empirical formula is
.
Thus, we can conclude that the empirical formula of the metal sulfide is
.
Answer:
A. Metallic bond
Explanation:
Think about it: copper and tin are both common metals. That's how we know it's a metallic bond!
Why not B: Covalent bonds are between two nonmetals.
Why not C: Ionic bonds are between a nonmetal and a metal.
Why not D: Paired bond isn't a common phrase in chemistry.
These atoms are isotopes, they have the same number of protons which means the atoms are of the same ELEMENT, but they have different numbers of neutrons.
<h3>Hi!</h3>
<h3>The correct options would be:</h3>
1, 3 and 4.
In an alpha decay, the atom's mass number is reduced by 4, and the atomic number is reduced by two following the emission of an alpha particle (2 protons and 2 neutrons).
In gamma decay, the atom releases energy spontaneously to stabilize itself, and this energy is released in the form of photons.
<h3>Hope this helps!</h3>
O - H
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