Answer:
56.9 mmoles of acetate are required in this buffer
Explanation:
To solve this, we can think in the Henderson Hasselbach equation:
pH = pKa + log ([CH₃COO⁻] / [CH₃COOH])
To make the buffer we know:
CH₃COOH + H₂O ⇄ CH₃COO⁻ + H₃O⁺ Ka
We know that Ka from acetic acid is: 1.8×10⁻⁵
pKa = - log Ka
pKa = 4.74
We replace data:
5.5 = 4.74 + log ([acetate] / 10 mmol)
5.5 - 4.74 = log ([acetate] / 10 mmol)
0.755 = log ([acetate] / 10 mmol)
10⁰'⁷⁵⁵ = ([acetate] / 10 mmol)
5.69 = ([acetate] / 10 mmol)
5.69 . 10 = [acetate] → 56.9 mmoles
Answer:
32
Explanation:
0.56dm of gas has 0.8g
22.4dm of gas Z has a mass of 22.4/0.56X0.8
the relative molecular mass of gas Z is 32
6.6ml will be the new volume if the pressure increases to 4 atm and the temperature are lowered to 200 K.
<h3>What is an ideal gas equation?</h3>
The ideal gas law (PV = nRT) relates the macroscopic properties of ideal gases. An ideal gas is a gas in which the particles (a) do not attract or repel one another and (b) take up no space (have no volume).
Given data:
Using equation:
Hence, 6.6ml will be the new volume if the pressure increases to 4 atm and the temperature are lowered to 200 K.
Learn more about the ideal gas equation here:
#SPJ1
Answer: 1.5 moles
Explanation: one mole Zn uses 2 moles HCl.
1.5 moles Zn uses 3.0 mol HCl. Then Zn is a limiting reactant
And produces equal amount of H2.
