The formula for potassium sulfide is K2S
Answer:
Only 4 %
Explanation:
Just about 4 percent of the known universe overall mass consists of atomic nuclei and is therefore described by chemical components. This proportion is around 15 percent of the total mass, with dark energy becoming the majority of the material .
Answer: The correct is 0.5 moles.
Explanation:
In an aqueous solution, the hydronium ion concentration is equivalent to the hydrogen ion concentration because the hydrogen ion exists as the hydronium ion. The pH of pure water is 7, and:
pH = -log[H+]
7 = -log[H+]
[H+] = 1 x 10⁻⁷
Therefore, the hydronium ion concentration in pure water is also 1 x 10⁻⁷.