Explanation:
I
have not yet learnt chemistry so sorry
Justification for your answer
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Chlorine is less reactive than fluorine because the outer electrons in a chlorine atom are further from the nucleus than the outer electrons in a fluorine atom. It is harder for a chlorine atom to gain an electron than it is for a fluorine atom.
There are three things to consider every single time relative reactivity is unknown; atomic radius, shielding, and number of electrons. The reactivity is the halogens ability to gain an electron, so number of electrons already in the atom plays a vital role. Chlorine has more electrons so repels a reacting electron with greater force than fluorine, making it less likely to react.
Fluorine also has fewer electron shells than chlorine, so there are fewer electrons between the positive nucleus and the reacting electron to essentiallly block, or weaken, the electromagnetic attraction. This is shielding. Lastly, fluorine is much smaller molecule than chlorine, and the shorter distance, or radius, between the nucleus and the electron again makes it more likely to attract the electron and react to gain a noble gas configuration.
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Answer:
In advance
middle
lower
Explanation:
These are the safety precautions needed when carrying out duties in the fume hood.
When planning and preparing to work in a fume hood (a locally designed area to reduce exposure to hazardous fumes). It is advisable to make all equipment readily available at your disposal <u>in advance</u> to reduce and minimize the raising and lowering of the hood sash at intervals.
It is also pertinent to understand that working in the<u> middle </u>of the work surface helps to promote the movement of air and keeps the area neat and tidy.
However, if any case where there is a need to get a new tool or equipment during the process of working in a fume hood, it is advisable to <u>lower </u>the sash at that point in time.
