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Chemistry
A Level

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
8147 Views

The pH of pure water can vary depending on the temperature it is held at. Does that mean pure water can be acidic or alkaline?

Interestingly, pure water will always be neutral, regardless of pH. To understand why, we have to properly look at what pH means. pH is a measure of the number of free H+ ions in a solution or liquid. The...

Answered by Sebastian N. Chemistry tutor
9460 Views

What are isotopes?

Isotopes are a variant of a particular chemical element in the Periodic Table. They have the same atomic number, therefore the same number of protons and electrons. However they have a different number of...

Answered by Priya A. Chemistry tutor
3444 Views

Anhydrous magnesium chloride, MgCl2, can absorb water to form the hydrated salt MgCl2.4H2O. Suggest one reason why the enthalpy change for this reaction cannot be determined directly by calorimetry.

Not possible to prevent some dissolving/ It is soluble / dissolves / other hydrates may form / difficulty to measure temperature change of a solid.

Answered by Alex H. Chemistry tutor
11021 Views

Why do first ionisation energies decrease down a group?

This is an example of remembering the basic trends of ionisation energies of different elements across the periodic table and applying this knowledge in detailWe take the Bohr model of the atom where the ...

Answered by Bence D. Chemistry tutor
1556 Views

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