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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

13363 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

3090 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

3082 Views

What is a phospholipid and how does it form part of the cell membrane?

The cell membrane is a complex material made up of three main components: the phospholipid bilayer, proteins, and cholesterol. The tadpole-shaped phospholipid is made up of a phosphate head attached to a ...

Answered by Joseph C. • Biology tutor

3722 Views