<span>The number of atoms in 4.75 moles of gold (Au) is found using Avogadro's number, which is 6.022Ă—1023 mol-1. Determine the number of atoms by multiplying 4.75 moles by Avogadro's number. The number of atoms in 4.75 moles of gold is 2.8605172125000205e24.</span>
pH of 0.048 M HClO is 4.35.
<u>Explanation:</u>
HClO is a weak acid and it is dissociated as,
HClO ⇄ H⁺ + ClO⁻
We can write the equilibrium expression as,
Ka = ![$\frac{[H^{+}] [ClO^{-}] }{[HClO]}](https://tex.z-dn.net/?f=%24%5Cfrac%7B%5BH%5E%7B%2B%7D%5D%20%5BClO%5E%7B-%7D%5D%20%20%7D%7B%5BHClO%5D%7D)
Ka = 4.0 × 10⁻⁸ M
4.0 × 10⁻⁸ M = 
Now we can find x by rewriting the equation as,
x² = 4.0 × 10⁻⁸ × 0.048
= 1.92 × 10⁻⁹
Taking sqrt on both sides, we will get,
x = [H⁺] = 4.38 × 10⁻⁵
pH = -log₁₀[H⁺]
= - log₁₀[ 4.38 × 10⁻⁵]
= 4.35
Answer:
c. Cr
Explanation:

The compound is containing
ion.
If acid reacts with it, CO_2 evolves.

therefore, Cr would form a precipitate when added to an aqueous solution of this compound. Cr2CO3 is the precipitate.
Answer:
HBr + H₂SO₄ → SO₂ + Br₂ + H₂O An oxidizing agent is a substance that itself becomes reduced and oxidizes the other chemical species in the reaction mixture. A reducing agent is similar, except that it becomes oxidized and reduces the other substance. In the reaction, the valency of bromine changes from -1 to 0, so it is oxidized
Explanation: