Top answers

What is the difference between 'le' and 'un' in french?

'Le', 'la', 'les' is used when you are asking or describing something in particular. "Can I have the blue pen?" - "Est-ce que je peux avoir LE stylo bleu?" - You only want the blue pen. &...
EK
Answered by Emma K. • French tutor
13616 Views

When do I use "tu" and when do I use "vous"?

Explanation: Both "tu" and "vous" mean "you" but "tu" is used for the singular of "you" and "vous" is used in two cases: the plural of "you&qu...
MM
Answered by Mathilde M. • French tutor
4097 Views

What is ecological validity?

Ecological validity is the extent to which research, or findings from an experiment, can be applied to real-life settings - i.e. the "real world". Lab studies often lack ecological validity as they...
BS
Answered by Beth S. • Psychology tutor
5271 Views

What is optical isomerism and how can you distinguish between optical isomers?

A molecule will exhibit optical isomerism if it contains a chiral centre / an asymmetric carbon atom - in other words, if it contains a carbon atom with 4 different groups attached. Due to this property, the...
BS
Answered by Beth S. • Chemistry tutor
47998 Views

What is the difference between covalent compounds and ionic compounds?

Covalent compounds contain atoms that share electrons - for example, hydrogen chloride (HCl) share electrons (one from each atom), in order to achieve a full set of 8 electrons in their outer shell. Covalent...
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Answered by Beth S. • Chemistry tutor
9578 Views