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Explain why a pH probe is required in a fermenter used for culturing micro-organisms.

It is important to monitor the pH of the fermenter to ensure this acidity can be detected and acid or alkali can be added accordingly to make sure the fermenter is at the optimum pH for the microorganisms...

Answered by Madeleine O. • Biology tutor

13429 Views

Give the key characteristic features of a prokaryotic cell.

Prokaryotic cells are usually 1-10 micrometers in size. Prokaryotic cells have a cell wall, which is usually complexed with a peptidoglycan layer. Prokayotic cells do not have a nucleus. Prokayotic cells ...

Answered by Branislav V. • Biology tutor

4039 Views

Describe the effects of changing the temperature on a reaction using Le Chatelier's princriple

Temperature: Exothermic reaction= energy given out to surroundings. Endothermic reaction= energy taken in from surroundings.

If say a reaction runs at 300 degrees and we increase the temperature to...

Answered by Branislav V. • Chemistry tutor

2496 Views

Express 5cosx - 3sinx in the form Rcos(x+a).

cos(x+a)=cosxcosa-sinxsina so cosa=5 sina=3 which means tana=3/5 a=0.54 RADIANS R=sqrt(5²+3²). =sqrt(34) so sqrt(34)cos(x+0.54)

Answered by Elizabeth H. • Maths tutor

16271 Views

A cyclist rides 10km. In the first 5km, they climb a hill, averaging 10km/h. In the second 5km, they descend the hill, averaging 30km/h. What is their average speed over the full 10km?

A common response from the student for the above question is: “I got 20km/h but it says it’s wrong! help i’m really confused”. The following two paragraphs will outline how I might attempt explain this id...

Answered by Shihabul B. • Physics tutor

3677 Views