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How do you describe the process of recrystallisation to purify a product?

When describing the process of recrystallisation, it is important that every step is mentioned. Firstly, the impure product must be dissolved in a minimum amount of hot solvent. The hot s...

Answered by Chris R. • Chemistry tutor

11406 Views

Electrons moving in a beam have the same de Broglie wavelength as protons moving in a separate beam. The proton beam moves at a speed of 3.1 x 10^4 m/s. What is the speed of the electrons?

From the data sheet, the de Broglie wavelength, 𝜆 = h/p = h/(mv)
The electron wavelength equals the proton wavelength so: 𝜆_e = 𝜆_p
So:

Answered by Alexandra G. • Physics tutor

2773 Views

Simplify √ 12 + √ 75

First, the surds need to be simplified. Surds can be simplified by finding the highest square number that is a factor of the number in the square root.√12 = √(4 x 3) = √4 x √3 = 2√3√75 = √(25 x 3) = √25 x...

Answered by Georgia R. • Maths tutor

14492 Views

Translate the following extract into French (The Economist)

For nearly three months, the formerly globe-trotting French president has scarcely left the country. Instead he has cleared his diary to criss-cross France, staging nearly a dozen town-hall meetings in a ...

Answered by Ombeline L. • French tutor

1834 Views

How do you know when to integrate by parts?

This is usually a good idea if you have an integral with two functions multiplied together when one of the functions differentiates to a constant (could take more than one differentiation).For example to ...

Answered by Dominic H. • Maths tutor

2789 Views