Answer:
pH =3.8
Explanation:
Lets call the monoprotic weak acid HA, the dissociation equilibria in water will be:
HA + H₂O ⇄ H₃O⁺ + A⁻ with Ka = [ H₃O⁺] x [A⁻]/ [HA]
The pH is the negative log of the H₃O⁺ concentration, we know the equilibrium constant, Ka and the original acid concentration. So we will need to find the [H₃O⁺] to solve this question.
In order to do that lets set up the ICE table helper which accounts for the species at equilibrium:
HA H₃O⁺ A⁻
Initial, M 0.40 0 0
Change , M -x +x +x
Equilibrium, M 0.40 - x x x
Lets express these concentrations in terms of the equilibrium constant:
Ka = x² / (0.40 - x )
Now the equilibrium constant is so small ( very little dissociation of HA ) that is safe to approximate 0.40 - x to 0.40,
7.3 x 10⁻⁶ = x² / 0.40 ⇒ x = √( 7.3 x 10⁻⁶ x 0.40 ) = 1.71 x 10⁻³
[H₃O⁺] = 1.71 x 10⁻³
Indeed 1.71 x 10⁻³ is small compared to 0.40 (0.4 %). To be a good approximation our value should be less or equal to 5 %.
pH = - log ( 1.71 x 10⁻³ ) = 3.8
Note: when the aprroximation is greater than 5 % we will need to solve the resulting quadratic equation.
Answer:
2.46 × 10²⁵ atoms H
Explanation:
Avagadro's Number: 6.022 × 10²³
Step 1: Find formulas
Hydrogen - H
Ammonium Sulfide - (NH₄)₂S
Step 2: Use Dimensional Analysis
=
Step 3: Simplify
We have 3 sig figs.
2.45616 × 10²⁵ atoms H ≈ 2.46 × 10²⁵ atoms H
Weathering definition= <span>wear away or change the appearance or texture of (something) by long exposure to the air.
Erosion definition= </span><span>the process of eroding or being eroded by wind, water, or other natural agents.
Deposition definition= </span>the action of deposing someone, especially a monarch.
these definitions are out of my textbook but in my own words.
Answer:
I'm pretty sure its a combination reaction!!
Explanation:
they generally form between metals and non metals like that^
