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When vaporised, isotopes of an element can be separated in a mass spectrometer. Name the three processes that occur in a mass spectrometer before the vaporised isotopes can be detected. State how each process is achieved. (6 marks)

Once the sample is vaporised, high energy electrons are fired at the sample which knocks off a loosely held electron. (1) This step is known as election impact ionisation. (2) Due to the presence of a cha...

Answered by Madalina F. • Chemistry tutor

4647 Views

Curve C has equation y=(9+11x)/(3-x-2x^2). Find the area of the curve between the interval (0, 1/2). State your answer in exact terms.

The word "area" should highlight that it is an integration question to the student. The interval asked for is (0,1/2) and so the curve should be integrated between that interval.The first task i...

Answered by Isha A. • Maths tutor

3068 Views

Describe how blood is pumped around the heart and the body.

Deoxygenated blood from the body is delivered to the right atrium by the vena cava. The right atrium contracts and blood flows into the right atrium. The right ventricle then contracts and blood is pumpe...

Answered by Bel R. • Biology tutor

2849 Views

What is involved in the fight or flight response?

The fight or flight response is triggered when the brain registers a threatening stimulus. It mobilizes the amygdala, sending a message to the hypothalamus which triggers activity in the sympathetic branc...

Answered by Lottie T. • Psychology tutor

3145 Views

How does the water potential in the medulla of the kidney remain lower than the water potential in the loop of Henle?

The loop of Henle is designed so that the water moves out of the thinner walled descending limb by osmosis and then ions such as Na+ and Cl- are actively transported out of the ascending limb. This active...

Answered by Oliver G. • Biology tutor

5911 Views