Answer:
6.22 × 10⁻⁵
Explanation:
Step 1: Write the dissociation reaction
HC₆H₅COO ⇄ C₆H₅COO⁻ + H⁺
Step 2: Calculate the concentration of H⁺
The pH of the solution is 2.78.
pH = -log [H⁺]
[H⁺] = antilog -pH = antilog -2.78 = 1.66 × 10⁻³ M
Step 3: Calculate the molar concentration of the benzoic acid
We will use the following expression.
Ca = mass HC₆H₅COO/molar mass HC₆H₅COO × liters of solution
Ca = 0.541 g/(122.12 g/mol) × 0.100 L = 0.0443 M
Step 4: Calculate the acid dissociation constant (Ka) for benzoic acid
We will use the following expression.
Ka = [H⁺]²/Ca
Ka = (1.66 × 10⁻³)²/0.0443 = 6.22 × 10⁻⁵
Answer: 162.8 grams
Explanation:
Magnesium nitrate has a chemical formula of Mg(NO3)2.
Given that:
Number of moles of Mg(NO3)2 = 1.1 moles
Mass in grams of Mg(NO3)2 = ?
For Molar mass of Mg(NO3)2, use atomic mass of magnesium = 24g, nitrogen = 14g, oxygen = 16g
Mg(NO3)2 = 24g + (14g + 16gx3) x 2
= 24g + (14g + 48g) x 2
= 24g + (62g) x 2
= 24g + 124g
= 148g/mol
Now, apply the formula:
Number of moles = Mass in grams / molar mass
1.1 moles = Mass / 148g/mol
Mass = 1.1 moles x 148g/mol
Mass = 162.8 grams
Thus, there are 162.8 grams of magnesium nitrate.
Answer:
B) 0.32 %
Explanation:
Given that:
Concentration = 1.8 M
Considering the ICE table for the dissociation of acid as:-
The expression for dissociation constant of acid is:
![K_{a}=\frac {\left [ H^{+} \right ]\left [ {CH_3COO}^- \right ]}{[CH_3COOH]}](https://tex.z-dn.net/?f=K_%7Ba%7D%3D%5Cfrac%20%7B%5Cleft%20%5B%20H%5E%7B%2B%7D%20%5Cright%20%5D%5Cleft%20%5B%20%7BCH_3COO%7D%5E-%20%5Cright%20%5D%7D%7B%5BCH_3COOH%5D%7D)
Solving for x, we get:
<u>x = 0.00568 M</u>
Percentage ionization = 
<u>Option B is correct.</u>
Answer:
Assign oxidation numbers to all atoms in the equation.
Compare oxidation numbers from the reactant side to the product side of the equation.
The element oxidized is the one whose oxidation number increased.
Explanation:
