B. released, forming bonds usually releases energy.
Answer:
2.25g of NaF are needed to prepare the buffer of pH = 3.2
Explanation:
The mixture of a weak acid (HF) with its conjugate base (NaF), produce a buffer. To find the pH of a buffer we must use H-H equation:
pH = pKa + log [A-] / [HA]
<em>Where pH is the pH of the buffer that you want = 3.2, pKa is the pKa of HF = 3.17, and [] could be taken as the moles of A-, the conjugate base (NaF) and the weak acid, HA, (HF). </em>
The moles of HF are:
500mL = 0.500L * (0.100mol/L) = 0.0500 moles HF
Replacing:
3.2 = 3.17 + log [A-] / [0.0500moles]
0.03 = log [A-] / [0.0500moles]
1.017152 = [A-] / [0.0500moles]
[A-] = 0.0500mol * 1.017152
[A-] = 0.0536 moles NaF
The mass could be obtained using the molar mass of NaF (41.99g/mol):
0.0536 moles NaF * (41.99g/mol) =
<h3>2.25g of NaF are needed to prepare the buffer of pH = 3.2</h3>
n = 1.5atm (15L) / .0821 (280k) = .98 mol NaCl
NaCl = 22.99g Na + 35.45g Cl = 58.44g NaCl
58.44g NaCl x .98 mol NaCl = 57.27g NaCl
Explanation:
hope you get it right :)
The answer is: supersaturated solution.
A supersaturated solution contains more of the dissolved substance than could be dissolved by the solvent under normal circumstances.
A way to dissolve more sugar into a solution is heating a solution.
The more heat is added to a system, the more soluble a substance (in this example sugar) becomes.
The solution will become supersaturated if this solution is suddenly cooled at a rate faster than the rate of precipitation.
For one a homogenous mixture cannot be separated using filtration. Hope this helps:)
