Oxygen carbon and hydrogen
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>
Answer:
I'm assuming atmospheric pressure, since it says she is measuring pressure exerted my atmospheric gases
In a chemical equation the coefficients represent the ration of the number of moles. therefore, if you have 16 moles of oxygen, you would have 32 moles of water.
Answer:
4.90 g
Explanation:
Given that:
volume of t-pentyl alcohol = 5 mL
the standard density of t-pentyl alcohol = 0.805 g/mL
Recall that:
density = mass(in wt) /volume
mass = density × volume
mass = 0.805 g/mL × 5 mL
mass = 4.03 g
Volume of HCl used = 12 mL
The reaction for this equation is shown in the image attached below.
From the reaction,
88.15 g of t-pentyl alcohol reacts with concentrated HCl to yield 106.59 g pf t-pentyl chloride.
4.03 g of t-pentyl alcohol forms,
of t-pentyl chloride.
Therefore,
Theoretical yield of t-pentyl chloride = 4.90 g
