Answer:Nhóm gồm tất cả các kim loại tan trong axit sunfuric đặc nóng nhưng không tan trong axit sunfuric lo
Al, Cu, Au.
Al, Fe, Cr.
Ag, Fe, Pt.
Ag, Cu, Hg.
Explanation:
We can find the principal level or lower level
using Rydberg's formula:
1/w = R(1/L² - 1/U²)
<span>where:</span>
<span>w is the
wavelength (93.8 nm),</span>
L is the lower energy level (unknown)
U the upper energy level (n= 6)
R is Rydberg's constant (10,967,758
waves per meter)
Substituing known values into the equation:<span>
1/(9.38 * 10^-8 m.) = 10,967,758(1/L² - 1-36) </span>
Using the solver function of the calculator to
get for L:
L = 0.999 <span>
so L = 1.
<span>The lower level is 1 (the ground state).</span></span>
I believe that it most likely would be D.
2Ag⁺(aq) + Mg(s)→ 2Ag(s) + Mg²⁺ (aq)
<h3>Further explanation</h3>
Given
Standard cell notation:
Mg(s) | Mg2+ (aq) || Ag+(aq)| Ag(s)
Required
a balanced redox reaction
Solution
At the cathode the reduction reaction occurs, the anode oxidation reaction occurs
In reaction:
Ag⁺ + Mg → Ag + Mg²⁺
half-reactions
- at the cathode (reduction reaction)
Ag⁺ (aq) + e⁻ ---> Ag (s) x2
2Ag⁺ (aq) + 2e⁻ ---> 2Ag (s)
- at the anode (oxidation reaction)
Mg (s) → Mg²⁺ (aq) + 2e−
a balanced cell reaction
<em>2Ag⁺(aq) + Mg(s)→ 2Ag(s) + Mg²⁺ (aq)
</em>
The answer should be D. Hope this helps!!