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Chemistry
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What is entropy and how is it used in chemistry?

Entropy (S) is a measure of disorder in a system. Any process, in this case a chemical reaction, is said to entropically favoured if the overall disorder in the system increases. This is usually when ther...

KS
Answered by Kashf S. Chemistry tutor
2885 Views

How and why does atomic radius vary in the periodic table?

Atomic radius increases down a group in the periodic table. This can be explained by a phenomenon called electron shielding. As the number of electron shells is increased down the group, the attraction be...

CS
Answered by Craig S. Chemistry tutor
5626 Views

Why is the boiling point of PH3 lower than that of NH3?

PH3 is not hydrogen bonded whereas NH3 is hydrogen bonded. Hydrogen bonding is the strongest type of covalent bonding.

AT
Answered by Anita T. Chemistry tutor
23741 Views

What is the trend in atomic radius of the elements across Period 3 and why does this occur?

The atomic radius of the elements decreases from sodium to argon. This is because the number of protons increases (sodium has 11, argon has 18) so the nuclear charge increases. Therefore, the attraction b...

CG
Answered by Chloe G. Chemistry tutor
53625 Views

What is the electronic configuration of a Calcium ion?

1s2,2s2,2p6,3s2,3p6

ZO
Answered by Zainab O. Chemistry tutor
6275 Views

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