Answer:
Phase changes typically occur when the temperature or pressure of a system is altered. When temperature or pressure increases, molecules interact more with each other. When pressure increases or temperature decreases, it's easier for atoms and molecules to settle into a more rigid structure.
Explanation:
Hope it helps UvU
The elements are listed in order of increasing the atomic number. Its the number that is the number of protons in the nucleus of an atom.
Answer:
molarity= 0.238 mol L-
Explanation:
The idea here is that you need to use the fact that all the moles of sodium phosphate that you dissolve to make this solution will dissociate to produce sodium cations to calculate the concentration of the sodium cations.
Na 3 PO 4 (aq) → Na + (aq) + PO3−4 (aq)
Use the molar mass of sodium phosphate to calculate the number of moles of salt used to make this solution.
3.25g⋅1 mole N 3PO4 163.9g = 0.01983 moles Na3 PO 4
Now, notice that every
1 mole of sodium phosphate that you dissolve in water dissociates to produce
3bmoles of sodium cations in aqueous solution.
To solve this problem,
we can use the Henderson-Hasselbalch Equation which relates the pH to the measure
of acidity pKa. The equation is given as:<span>
<span>pH = pKa + log ([base]/[acid]) ---> 1</span></span>
Where,
[base] = concentration
of C2H3O2
in molarity or moles
<span>[acid] = concentration of HC2H3O2 in molarity or moles</span>
For the sake of easy calculation, let us assume that:
[base] = 1
[acid] = x
<span>
Therefore using equation 1,
4.24 = 4.74 + log (1 / x)
<span>log (1 / x) = - 0.5
1 / x = 0.6065 </span></span>
x =
1.65<span>
The required ratio of C2H3O2 /HC2H3O2 <span>
is 1:1.65 or 3:5. </span></span>
