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Why is a nucleophilic substitution reaction between ammonia and benzene unlikely?

A nucleophilic substitution reaction is when a nucleophile (an electron pair donor) replaces an atom or part of a molecule. In this scenario ammonia (NH₃) is the nucleophile as it contains a lo...

Answered by Archit S. • Chemistry tutor

10679 Views

Describe how the presentation of a virus antigen on a cell leads to the secretion of antibodies against this viral antigen

3 mark question - remember to use key words/phrases the examiner will be looking for to give you the marks. Be concise and specific in your answer - make it as easy as possible for the examiner.

Answered by Eleanor M. • Biology tutor

23713 Views

Give two factors which aid the fossilization process, explaining how each increases preservation potential.

Rapid burial of the organic material will prevent any erosion or scavenging occurring, allowing the organic material to become encased in rock and become more likely too be preserved.Becoming buried in fi...

Answered by Ciaran C. • Geology tutor

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Find the first three terms of the binomial expansion of (3 + 6x)^(1/2).

To find the binomial expansion of this expression we need to use a formula. The formula states that for expressions of (1 + x)ⁿ it can be written as: 1 + nx + (n(n-1)x²)/2 ...
A...

Answered by Brendan W. • Maths tutor

6298 Views

Using implicit differentiation, write the expression "3y^2 = 4x^3 + x" in terms of "dy/dx"

To differentiate this expression with respect to "x", any terms comprising of an "x" must multiply their powers with their numerical values and subtract 1 from the power. However to di...

Answered by Brendan W. • Maths tutor

3892 Views