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4 years ago

Calculate the pH of a 0.30 M NaF solution. The Ka value for HF is 7.2*10^-4

1 answer:

5 0

We are given with the equilibrium constant of acid, HF and is asked to calculate the pH of 0.30 M NaF solution. The formula to be followed is
Ka = [H+][F-]/[HF]Ka = 7.2 x 10 -4 = x^2/[0.3-x]x = [H+]= pH = -log (H+) = 1.84

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Write the formulas of the three singly chlorinated isomers formed when 2,2-dimethylbutane reacts with Cl2 in the presence of lig

Tems11 [23]

The molecule with same molecular formula but different arrangement of atoms is said to be an isomer.

When 2,2-dimethylbutane reacts with chlorine in the presence of light gives three isomers that is $CH_{3}C(CH_{3})_{2}CHClCH_{3}$ (3-chloro-2,2-dimethylbutane), $ClCH_{2}C(CH_{3})_{2}CH_{2}CH_{3}$ (1-chloro-2,2-dimethylbutane) and $ClCH_{2}CH_{2}C(CH_{3})_{2}CH_{3}$ (1-chloro-3,3-dimethylbutane).

In above case, the molecular formula of all isomers are same i.e. $C_{6}H_{13}Cl$ but chlorine is arranged in different positions of carbon. Thus, results isomers.

The reaction is shown in the image.

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3 years ago

A methanol-water mixture is to be flash distilled at 1 atm. If the feed is 25 mole %methanol, what are the liquid and vapor comp

frozen [14]

Answer:

Explanation:

Given that:

The distillation is carried out at a pressure of 1 atm

The feed harbors 25% mole of methanol (z)

The total moles of feed is usually 100 moles

In the system, we have both methanol and water

Using the total mole balance for the distillation column.

Fz = Lx + Vy

where;

F = amount of feed

z = mole fraction of ethanol (in feed)

L = amount of liquid product out of the column

V = amount of vapor product out of the column

x = mole fraction of methanol out of the liquid

y = mole fraction of methanol out of the vapor.

SO;

(a)

If all the feed is vaporized, then the vapor will likely have the same composition as the feed.

(b)

If no vaporization of the feed takes place, then the bottoms moving out of the column contains the same composition as the feed.

(c)

If 1/3 of the feed is vaporized; then 2/3 of the feed is at the bottom.

The balance equation would be:

$Fz = (\dfrac{2}{3}F) x + (\dfrac{1}{3}F)y \\ \\ z = \dfrac{2}{3}x+\dfrac{1}{3}y$

Replacing z = 0.25; we have:

$0.25 = \dfrac{2}{3}x+\dfrac{1}{3}y$

0.75 = 2x + y

(d)

If 2/3 of the feed is vaporized;

Then:

$Fz = (\dfrac{1}{3}F) x + (\dfrac{2}{3}F)y \\ \\ z = \dfrac{1}{3}x+\dfrac{2}{3}y$

replacing z = 0.25

$0.25 = \dfrac{1}{3}x+\dfrac{2}{3}y$

0.75 = x + 2y

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3 years ago

What begins to happen to radioactive uranium as soon as a mineral containing it crystallizes from magma?

Aleonysh [2.5K]

The radioactive uranium decays into its daughter product, lead. It would do this in magma as well, as nuclear decay depends on forces within the atom, not on the phase of the material in which the atom is a part.

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3 years ago

What three things happen to plates at the plate boundaries (where two or more plates come together)?

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Explanation:

a. A divergent plate boundary process takes place

b. A convergent plate boundary process takes place

c. A transform plate boundary process takes place

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3 years ago

Chlorine gas is added to a large flask to a pressure of 1.85 atm, at a temperature of 322 K. Phosphorus is added, and a reaction

AVprozaik [17]