Answer:
0.42%
Explanation:
<em>∵ pH = - log[H⁺].</em>
2.72 = - log[H⁺]
∴ [H⁺] = 1.905 x 10⁻³.
<em>∵ [H⁺] = √Ka.C</em>
∴ [H⁺]² = Ka.C
∴ ka = [H⁺]²/C = (1.905 x 10⁻³)²/(0.45) = 8.068 x 10⁻⁶.
<em>∵ Ka = α²C.</em>
Where, α is the degree of dissociation.
<em>∴ α = √(Ka/C) </em>= √(8.065 x 10⁻⁶/0.45) = <em>4.234 x 10⁻³.</em>
<em>∴ percentage ionization of the acid = α x 100</em> = (4.233 x 10⁻³)(100) = <em>0.4233% ≅ 0.42%.</em>
Answer:
Explanation:
None of the statement is true for both chemical and nuclear reactions. In chemical reactions, mass is always conserved and the type of atoms are also conserved.
Its A because I did it on connexus
If 30 grams of KCl is dissolved at 10°C, 14 g of KCl should be added to make a saturated solution at 60 °C.
<h3>What is a saturated solution?</h3>
A saturated solution is a solution in which there is so much solute that if there was any more, it would not dissolve. Its concentration is the same as the solubility at that temperature.
- Step 1. Calculate the mass of water.
At 10 °C, the solubility is 31.2 g KCl/100 g H₂O.
30 g KCl × 100 g H₂O/31.2 g KCl = 96 g H₂O
- Step 2. Calculate the mass of KCl required to prepare a saturated solution at 60 °C.
At 60 °C, the solubility is 45.8 g KCl/100 g H₂O.
96 g H₂O × 45.8 g KCl/100 g H₂O = 44 g KCl
- Step 3. Calculate the mass of KCl that must be added.
44 g - 30 g = 14 g
If 30 grams of KCl is dissolved at 10°C, 14 g of KCl should be added to make a saturated solution at 60 °C.
Learn more about saturated solutions here: brainly.com/question/24564260
Answer:
Na
Explanation:
sodium has mass number 23 and atomic number 11 so number of protons =number of electrons =atomic number which is 11 and number of neutrons=mass number-number of protons =23-11=12