Answer:
First statement is true:
- <u><em>NH₄ would be expected to have polar covalent bonds with a partial positive charges on the H atoms.</em></u>
Explanation:
Nitrogen (N) and hydrogen (H) are two nonmetals; thus, it should be a hint to assert that they form a covalent bond.
The difference in <em>electronegativities</em> between<em> N</em> and <em>H </em>is <em>3.0</em> - <em>2.1</em> = 0.9.
That makes that the bonds be <em>polar</em>. Ions are not formed because to transfer the electrons from one atom to the other (to form ionic bonds) requires an electronegativity difference greater than about 1.7.
Since N is more electronegative than H, in the molecule <em>NH₄</em>, each N atom will pull the electron density toward itself acquiring a partial negative charge and leaving H atoms with a partial positive charge.
Thus, each NH bond is<em> polar covalent with a partial positive charge on the H atoms</em> (first statement from the choices).
Your answer would be
Speed requires distance. Velocity requires direction
I hope this helps!
Answer:
Explanation:
To calculate pH you need to use Henderson-Hasselbalch formula:
pH = pka + log₁₀ ![\frac{[A^-]}{[HA]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BA%5E-%5D%7D%7B%5BHA%5D%7D)
Where HA is the acid concentration and A⁻ is the conjugate base concentration.
The equilibrium of acetic acid is:
CH₃COOH ⇄ CH₃COO⁻ + H⁺ pka: 4,75
Where <em>CH₃COOH </em>is the acid and <em>CH₃COO⁻ </em>is the conjugate base.
Thus, Henderson-Hasselbalch formula for acetic acid equilibrium is:
pH = 4,75 + log₁₀ ![\frac{[CH_{3}COO^-]}{[CH_{3}COOH]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BCH_%7B3%7DCOO%5E-%5D%7D%7B%5BCH_%7B3%7DCOOH%5D%7D)
a) The pH is:
pH = 4,75 + log₁₀ ![\frac{[2 mol]}{[2 mol]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5B2%20mol%5D%7D%7B%5B2%20mol%5D%7D)
<em>pH = 4,75</em>
<em></em>
b) The pH is:
pH = 4,75 + log₁₀ ![\frac{[2 mol]}{[1mol]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5B2%20mol%5D%7D%7B%5B1mol%5D%7D)
<em>pH = 5,05</em>
<em></em>
I hope it helps!
