Sulfur possesses 16 electrons in its ground state. The first shell of sulfur has 2 electrons. The next shell has 8 electrons. The third and final shell of sulfur has 6 electrons. The electronic configuration is written as:
1s², 2s², 2p⁶, 3s², 3p⁴
This means that sulfur exhibits a valency of -2, which is true in many cases.
We calculate for the number of moles of water given its mass by dividing the given mass by the molar mass.
n water = (36.04 g) / (18 g/mol)
n water = 2 mols
From the given balanced equation, every 6 moles of water produced will require 7 moles of oxygen.
n oxygen = (2 mols H2O) x (7 moles O2 / 6 moles H2O)
n oxygen = 2.33 mols O2
Answer:

Explanation:
The formula for molality is:

There are 0.210 moles of KBr and 0.075 kilograms of pure water.

Substitute the values into the formula.

Divide.

The molality is <u>2.8 moles per kilogram</u>
The answer is Hydrogen
This is what happens when acids react with metals