Answer:
a. Phosphoric Acid
b. Acetic Acid
c. Hypochlorous Acid
Explanation:
A buffer works when the pH of this one is in pKa ± 1. That means, to find which buffer system works in some pH you need to find pKa:
pKa = -log Ka
<em>pKa Acetic acid:</em>
-log1.8x10⁻⁵ = 4.74
<em>pKa phosphoric acid:</em>
-log7.5x10⁻³ = 2.12
<em>pKa hypochlorous acid:</em>
-log3.5x10⁻⁸ = 7.46
a. For a pH of 2.8 the best choice is phophoric acid because its effective range is: 1.12 - 3.12 and 2.8 is between these values.
b. pH 4.5. Acetic acid. effective between pH's 3.74 - 5.74
c. pH 7.5. Hypochlorous acid that works between 6.46 and 8.46
Answer:
photosphere
Explanation:
photosphere
There are 3 main layers of the Sun that we can see. They are the photosphere, the chromosphere and the corona. Together they make up the "atmosphere" of the Sun. The part of the Sun that glows (and that we see with the naked eye) is called the photosphere
Answer:
Mg
Explanation:
The standard reduction potentials are
<u>E°/V
</u>
Au³⁺(aq ) + 3e⁻ ⟶ Au(s); 1.42
Hg²⁺(aq) + 2e⁻ ⟶ Hg(l); 0.85
Ag⁺(aq) + e⁻ ⟶ Ag(s); 0.80
Cu²⁺(aq) + 2e⁻ ⟶ Cu(s); 0.34
Mg2+(aq) + 2e- ⟶ Mg(s); -2.38
The more negative the standard reduction potential, the stronger the metal is as a reducing agent.
Mg is the only metal with a standard reduction potential lower than that of Cu, so
Only Mg will react spontaneously with Cu²⁺.
1. rancidification fixation of water is CHEMICAL CHANGE
2. Tearing of paper is PHYSICAL CHANGE
3. Rusting if iron is CHEMICAL CHANGE
4. Electrolysis of water is CHEMICAL CHANGE
<span>Hydroxy group..
... :):) ....</span>