Answer:
hey...
Explanation:
Sodium carbonate (Na2CO3), also known as washing soda, can soften both temporary and permanent hard water.
Answer
2.0 x 10²³ molecules.
Explanation
Given:
The number of moles of theobromide measured out = 0.333 moles.
MM of theobromide = 180.8 g/mol
What to find:
The number of molecules of theobromide the student measured.
To go from moles to molecules, multiply the number of moles by Avogadro's number.
The Avogadro's number = 6.02 x 10²³
1 mole of theobromide contains 6.02 x 10²³ molecules.
So, 0.333 moles of theobromide measured out will have (0.333 x 6.02 x 10²³) = 2.0 x 10²³ molecules.
Answer:
(a) The anode electrode which comprises the zinc electrode being placed in a water solution with low oxygen concentration.
(b) Cathodic reaction is: 
⇒ 
Anodic reaction is: 
⇒
Explanation:
In the given problem, we have an oxygen-concentration cell consisting of two zinc electrodes. One is immersed in a water solution with a low oxygen concentration and the other in a water solution with a high oxygen concentration. The zinc electrodes are connected by an external copper wire.
(a) Which electrode will corrode?
The electrode that will corrode is the anode electrode which comprises the zinc electrode being placed in a water solution with low oxygen concentration.
(b) Write half-cell reactions for the anodic reaction and the cathodic reaction.
Cathodic reaction is: ⇒
Anodic reaction is: ⇒
Answer:
Ka = 1.39x10⁻⁶
Explanation:
A monoprotic acid, HX, will be in equilibrium in an aqueous medium such as:
HX(aq) ⇄ H⁺(aq) + X⁻(aq)
<em>Where Ka is:</em>
Ka = [H⁺] [X⁻] / [HX]
<em>Where [] is the molar concentration in equilibrium of each specie.
</em>
The equilibrium is reached when some HX reacts producing H+ and X-, that is:
[HX] = 1.64M - X
[H⁺] = X
[X⁻] = X
As pH is 2.82 = -log [H⁺]:
[H⁺] = 1.51x10⁻³M:
[HX] = 1.64M - 1.51x10⁻³M = 1.638M
[H⁺] = 1.51x10⁻³M
[X⁻] = 1.51x10⁻³M
And Ka is:
Ka = [1.51x10⁻³M] [1.51x10⁻³M] / [1.638M]
<h3>Ka = 1.39x10⁻⁶</h3>
