Answer:
See explaination
Explanation:
Go to the attached file for the detailed and step by step solution of the given.
To get this it helps to know the electronegativity numbers of the elements but it isn't required. You just need to know that Fluorine is the most electronegative element and that the farther away from Fluorine you are on the periodic table, the less electronegative you get. The one exception to this rule is hydrogen with actually has an electronegativity of 2.1 while lithium has one of 1.0. Also the higher difference in electronegativity between two atoms the more polar the bond is.
Now to start the question. H-Br could be a contender since H has an electronegativity number of 2.1 and Br is relatively close to Fluorine so we'll put that one aside for now. H-Cl knocks out A because both bonds have H but one bond has Br and the other has Cl. Cl is closer to Fluorine than Br so answer B is the contender now. For answer C, I and Br are too close to have a higher electronegativity difference than H-Cl so that one isn't it. Finally for answer D, I is much closer to Cl than H is so the electronegativity difference is much less, making your answer B.
In 1 mole of magnesium there are Avogadro's number of atoms are present.
Avogadro's number = 6.023 x 10²³
1 mole = 6.023 x 10²³ atoms
3.75 moles = 3.75 x 6.023 x 10²³
=2.26 x 10²⁴
So, in 3.75 moles of magnesium there are 2.26 x 10²⁴ atoms of magnesium are present.
Answer:
Concentration: 0.185M HX
Ka = 9.836x10⁻⁶
pKa = 5.01
Explanation:
A weak acid, HX, reacts with NaOH as follows:
HX + NaOH → NaX + H2O
<em>Where 1 mole of HX reacts with 1 mole of NaOH</em>
To solve this question we need to find the moles of NaOH at equivalence point (Were moles HX = Moles NaOH).
18.50mL = 0.01850L * (0.20mol / L) = 0.00370 moles NaOH = Moles HX
In 20.0mL = 0.0200L =
0.00370 moles HX / 0.0200L = 0.185M HX
The equilibrium of HX is:
HX(aq) ⇄ H⁺(aq) + X⁻(aq)
And Ka is defined as:
Ka = [H⁺] [X⁻] / [HX]
<em>Where [H⁺] = [X⁻] because comes from the same equilibrium</em>
As pH = 2.87, [H+] = 10^-pH = 1.349x10⁻³M
Replacing:
Ka = [H⁺] [H⁺] / [HX]
Ka = [1.349x10⁻³M]² / [0.185M]
Ka = 9.836x10⁻⁶
pKa = -log Ka
<h3>pKa = 5.01</h3>
Answer:iron and oxygen combining to make rust. vinegar and baking soda combining to make sodium acetate, carbon dioxide and water
Explanation:
