The predicted order of ionization energies is Li > Na > K > Rb
<em>Atomic size increases as you go down a Group</em> (see image). We are adding electrons to increasingly larger shells.
The valence electrons are further from the attraction of the nucleus, so they are less tightly held.
Thus, <em>Li has the highest ionization energy</em> and <em>Rb the lowest</em>.
Answer:
An acid is a substance that releases H⁺ in aqueous solution.
Explanation:
There are different acid-base theories, such as Arrhenius, Bronsted-Lowry, Lewis, etc.
According to the Arrhenius theory, an acid is a substance that releases H⁺ in aqueous solution.
HCl(aq) → H⁺(aq) + Cl⁻(aq)
On the other hand, according to the Arrhenius theory, a base is a substance that releases OH⁻ in aqueous solution.
NaOH(aq) → Na⁺(aq) + OH⁻(aq)
Answer:
Explanation:
We must look up the standard reduction potentials for the half-reactions.
<u> ℰ° </u>
Cr₂O₇²⁻ + 14H⁺ + 6e⁻ ⇌ 2Cr³⁺ + 7H₂O 1.36
Cl₂ + 2e⁻ ⇌ 2Cl⁻ 1.35827
2IO₃⁻ + 12H⁺ + 10e⁻ ⇌ I₂ + 6H₂O 1.195
Fe³⁺ + e⁻ ⇌ Fe²⁺ 0.771
(a) Cr³⁺/Cl₂
We reverse the sign of ℰ° for the oxidation half-reaction. Then we add the two half-reactions and their ℰ° values.
<u> ℰ°/V </u>
2Cr³⁺ + 7H₂O ⇌ Cr₂O₇²⁻ + 14H⁺ + 6e⁻ -1.36
<u>Cl₂ + 2e⁻ ⇌ 2Cl⁻ </u> <u>1.358 27
</u>
2Cr³⁺ + 3Cl₂ + 7H₂O ⇌ Cr₂O₇²⁻ + 6Cl⁻ + 14H⁺ 0.00
(b) Fe²⁺/IO₃⁻
<u> ℰ°/V
</u>
Fe²⁺ ⇌ Fe³⁺ + e⁻ -0.771
<u>2IO₃⁻ + 12H⁺ + 10e⁻ ⇌ I₂ + 6H₂O </u> <u> 1.195
</u>
10Fe²⁺ + 2IO₃⁻ + 12H⁺ ⇌ 10Fe³⁺ + I₂ + 6H₂O 0.424
The ℰ° values for the cells are