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Why do melting points decrease down the group 1 and increade down the group 7? (core syllabus: Periodicity)

Elements in the group one (i.e. alkali metals from lithium to francium) exhibit metallic bonding: the positive nuclei are held together thanks to the attraction to delocalised electrons. As the number of ele...
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Answered by Paulina M. • Chemistry tutor
97961 Views

How do you know if you need an accent on 'a' or not?

Is it the verb 'avoir' or the preposition 'à'? To know which one to choose there is an easy question: can I say 'avait' instead of a/à? If the answer is yes, then it's the verb and it doesn't have an accent....
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Answered by Adeline C. • French tutor
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Why do some verbs take 'etre' in the perfect tense? And how can I memorise them?

The majority of French verbs are take a conjugated form of the verb 'avoir' (to have) when forming the perfect tense, similarly to English. However, there is an important minority of verbs that use a conjuga...
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Answered by Henry P. • French tutor
6987 Views

Difference between prokaryote and eukaryote?

Prokaryotes do not have a membrane bound nucleus, eukaryotes do. Prokaryotes have plasmids. Prokaryotes have smalled ribosomes than eukaryotes. Eukaryotes have more organelles than prokaryotes. I.e. eukaryot...
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Answered by Laurence D. • Biology tutor
4564 Views

Describe blood supply to the liver?

The liver is supplied by the hepatic artery bringing oxygenated blood to it. The liver is also supplied by the hepatic portal vein. This brings the absorbed nutrients from the small and large intestine to th...
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Answered by Laurence D. • Biology tutor
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