<u>Ans: Acetic acid = 90.3 mM and Sodium acetate = 160 mM</u>
Given:
Acetic Acid/Sodium Acetate buffer of pH = 5.0
Let HA = acetic acid
A- = sodium acetate
Total concentration [HA] + [A-] = 250 mM ------(1)
pKa(acetic acid) = 4.75
Based on Henderson-Hasselbalch equation
pH = pKa + log[A-]/[HA]
[A-]/[HA] = 10^(pH-pKa) = 10^(5-4.75) = 10^0.25 = 1.77
[A-] = 1.77[HA] -----(2)
From (1) and (2)
[HA] + 1.77[HA] = 250 mM
[HA] = 250/2.77 = 90.25 mM
[A-] = 1.77(90.25) = 159.74 mM
Answer:
0.683 moles of the gas are required
Explanation:
Avogadro's law relates the moles of a gas with its volume. The volume of a gas is directely proportional to its moles when temperature and pressure of the gas remains constant. The law is:
V₁n₂ = V₂n₁
<em>Where V is volume and n are moles of 1, initial state and 2, final state of the gas.</em>
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Computing the values of the problem:
1.50Ln₂ = 5L*0.205mol
n₂ = 0.683 moles of the gas are required
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Answer:
The number of moles: 0.25442 moles
Explanation:
One mole of Neon gas will occupy 22.4 at STP.
5.699L consists of
= 0.25442 moles.
M=n(pie)/RT
n=osmotic pressure(1.2 atm)
M=molar of the solution
R=gas constant(0.0821)
T= temperature in kelvin 25+273
M=[1.2atm /(0.0821L atm/k mol x 298k)]=0.049mol L
M= moles of the solute/ litres of solution(250/1000)
0.049= y/0.25
moles of solute is therefore =0.01225mol
molar mass=33.29 g/0.01225mol=2.7 x10^3g/mol