Answer:
The answer is B
Explanation:The answer is B because the color would be irreversible.
Answer:
pH = 2.
Explanation:
A weak acid is in equilibrium with its ions in a solution, so it must have an equilibrium constant (Ka). And, pKa = -logKa
Ka = 10⁻⁴
So, for CH₃COOH the equilibrium must be:
CH₃COOH(aq) ⇄ H⁺(aq) + CH₃COO⁻(aq)
1 M 0 0 Initial
-x +x +x Reacted
1-x x x Equilibrium
And the equilibrium constant:
![Ka = \frac{[H+]x[CH3COO-]}{[CH3COOH]}](https://tex.z-dn.net/?f=Ka%20%3D%20%5Cfrac%7B%5BH%2B%5Dx%5BCH3COO-%5D%7D%7B%5BCH3COOH%5D%7D)
Supposing x << 1:
10⁻⁴ = x²
x = √10⁻⁴
x = 10⁻² M, so the supposing is correct.
So,
pH = -log[H⁺]
pH = -log10⁻²
pH = 2
Explanation:
First, we need to calculate the number of moles of sodium carbonate we have in a 25 g sample. To calculate this, we will
find the molar mass of sodium carbonate (Na2CO3):
⇒ 2 × Molar mass of sodium + Molar mass of carbon + 3×molar mass of oxygen
⇒ 2 × 23 + 12 + 3 × 16
⇒ 46 + 12 + 48
⇒ 106g/mol
Thus, the molar mass of Na2CO3 is 106g/mol.
Therefore, number of moles = 25 ÷ 106
=> 0.2358 mol
Now, we know that every mole of Na2CO3 have 0.2358 moles of Na+ ions. Hence, total moles of Na2CO3 is 0.4716 moles
Number of ions present = 6.022 × 1023 × 0.4716 mol = 2.84 × 1023ions
Answer:
1.80 x 10^24 atoms
Explanation:
3moles × 6.022×10^23 atoms/mole
N=2 (always first number), l=1 (corresponds to p), ml=(-1 to 1)
