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How does a fractional distillation tower work?

The crude oil, which is composed of a mixture of different hydrocarbons, is heated in the bottom of the tower, so that hydrocarbons with lower boiling points boil off first. The tower gets gradually colde...

Answered by David K. • Chemistry tutor

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The acid dissociation constant, Ka, of ethanoic acid is 1.78 x 10^-5 at 298K. Given that the concentration of a sample of ethanoic acid is 0.4moldm^-3, calculate its pH at 298K.

Using the acid dissociation equation, Ka = [H+][A-]/[HA]. (where Substitute the known values into the concentration to give 1.78x10^-5= [H+][A-]/0.4 . Because the acid is dissociating in solutio...

Answered by Sita R. • Chemistry tutor

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A Solution of NaOH had a concentration of 40g/dm3. What mass of NaOH would there be in 250cm3 of the solution?

The two volumes in this question are in different units, so first we need to get both our volumes on the same page. remember 10cm = 1dm so 1000cm³ = 1dm³ (10³cm³

Answered by Eme H. • Chemistry tutor

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What is ionic bonding and what are the characteristics of this type of bonding?

The definition of ionic bonding is the electrostatic attraction between oppositely charged particles. This occurs between a non-metal and a metal where the electron transfer goes from a metal to a non-met...

Answered by Nicole L. • Chemistry tutor

1891 Views

Explain what occurs when an acid reacts with an alkali, in terms of ions and molecules. Also show the equation.

Answerhydrogen ions from the acid react with hydroxide ions from the alkali to form water.
H+. + OH- —> H20
ExplanationIt is important to remember that when an acid reacts wit...

Answered by Filip S. • Chemistry tutor

29596 Views