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A buffer solution was formed by mixing 20.0 cm^3 of sodium hydroxide solution of concentration 0.100 mol dm^–3 with 25.0 cm^3 of ethanoic acid of concentration 0.150 mol dm^–3. CH3COOH + NaOH---CH3COONa + H2O Calculate the pH of this buffer solution.

Ka for ethanoic acid = 1.74 × 10–5 mol dm^–3 also given in question. moles = concentration x volume / 1000Ka = [H+] [A-]/[HA]pH = -log [H+]
initial moles:NaOH: 20x0.1/1000 = 0.002molCH_...

Answered by • Chemistry tutor

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How do I approach analysing an unseen poem?

The very first thing you need to do is purely read it through in order to get an understanding of the poem. I'd recommend not even trying to think too technically at this point, but rather notice what eff...

Answered by Romilly L. • English Literature tutor

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Deine deutsche Freundin hat dir eine Postkarte geschrieben. Sie hat dich gefragt wo du gerne in den Urlaub fahren möchtest. Beschreibe was dein Traumurlaub wäre, wieso du gerne dahin fahren möchtest und was du dort machen würdest.

Am liebsten würde ich nach Egypten fahren, weil ich in meinem Leben noch nie eine Pyramide gesehen habe. Die egyptische Kultur und Geschichte finde ich auch fascinierend. Meine große Schwester zieht nächs...

Answered by Katherine R. • German tutor

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Solve the simultaneous equations: 2x + y = 5 , x + 4y = -22

Showing each step of working is important.First, we need to rearrange one of the equations to solve for x or y.If we rearrange the first equation to solve for y in terms of x we get: y = 5 - 2x ( by subtr...

Answered by Joel F. • Maths tutor

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What is diffusion?

Diffusion is the process by which a molecule moves from an area of high concentration to an area of low concentration, down a concentration gradient. Any gas or liquid can move by diffusion, and no energy...

Answered by Joel F. • Biology tutor

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