Answer:
0.32M
Explanation:
<u>Step 1:</u> Balance the reaction
K2CO3 + Ba(NO3)2 ⇔ KNO3 + BaCO3
We have a 20 mL 0.2 M K2CO3 and a 30mL 0.4M Ba(NO3)2 solution
SinceK2CO3 is the limiting reactant, there will remain Ba(NO3)2 after it's consumed and produced KNO3 + BaCO3
<u>Step 2: </u>Calculate concentration
To find the concentration of the barium cation we use the following equation:
Concentration = moles of the <u>solute</u> / volumen of the <u>solution</u>
<u />
<u>[Ba2+] </u> = (20 * 10^-3 * 0.2M + 30 * 10^-3 * 0.4M) / ( 20 + 30mL) *10^-3
[Ba2+] = 0.32 M
The concentration of Barium ion in solution is 0.32 M
Let A be the 80% solution and B be the 20% solution and P be the produce solution of 70%. Va and Vb and Vp are the volumes of A and B and P respectively.
Va + 60 = Vp
0.7Vp = 0.8Va + 0.2(60)
Substituting the value of Vp from the first equation:
0.7(Va + 60) = 0.8Va + 12
30 = 0.1Va
Va = 300 gallons
The factor that is generally responsible for higher melting point is intermolecular forces. The compounds that are covalent in nature are made of molecules rather than ions. It has been seen that some of the covalent compounds have polar molecules at one end, due to which the one end has more electronegative force than the other. The electrostatic force that is bounding the compound is the main cause of higher melting point of this compound. So it is true that with the increase of polarity of a compound creates higher melting point. .. hope I helped
<span>You use the Henderson - Hasselbalch equation
pH = pKa + log ([salt]/[acid])
pKa = -log (8.2*10^-5) = 4.081
pH = 4.081 + (0.590/0.190)
pH = 4.081 + log 3.105
pH = 4.081 + 0.49206
pH = 4.573</span>