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A buffer solution is made with a pH of 5.000. Solid sodium ethanoate, CH3COONa, is added to 400 cm^3 of 0.200 mol dm^–3 ethanoic acid (Ka = 1.75 × 10^–5 mol dm^–3). Calculate the mass of sodium acetate that must be dissolved in the acid to prepare this

There are three steps:
Calculate [CH₃COO^–] using the equation for K_aCalculate the moles of CH₃COO^– using the equation concentration = moles/volu...

Answered by Felix B. • Chemistry tutor

15170 Views

Given that (2x-1) : (x-4) = (16x+1) : (2x-1), find the possible values of x

The question tells us the ratio between two algebraic expressions is the same as the ratio between 2 other algebraic expressions. So, we can re-write the equation as (2x-1)/(x-4) = (16x+1)/(2x-1)Re-arrang...

Answered by Pav M. • Maths tutor

18770 Views

How does F Scott Fitzgerald convey an admiration for excessive wealth in the opening scene of Tender is the Night?

The surreal image of this place aids the clear portrayal of excessive wealth, prominent throughout, which is closely linked to the worshipping of luxury. For example, the "large, proud, rose-coloured...

Answered by Helena L. • English Literature tutor

3992 Views

How are nerve impulses transmitted across a synapse?

Nerve impulses travel in one direction from the pre-synaptic to the post-synaptic neuron across a gap called a synapse. This is done to continue a nerve impulse so that it can reach its destination in the...

Answered by Elizabeth H. • Biology tutor

8387 Views

The curve C has equation x^2 – 3xy – 4y^2 + 64 = 0; find dy/dx in terms of x and y, and thus find the coordinates of the points on C where dy/dx = 0

Start by differentiating x² – 3xy – 4y² + 64 = 0 with respect to x to obtain an equation in x, y and dy/dx:
2x – 3y – 3x.dy/dx – 8y.dy/dx = 0 [use the product rule to differe...

Answered by Felix B. • Maths tutor

13368 Views