Which compound is an exception to the octet rule? h2o hcl ccl4 clf3

is an exception to the octet rule.

Explanation: Octet rule is general rule for most of the atoms which says that the atoms must have 8 electrons in their valence shell in order to be stable. For this they can gain, loose of share the electrons from the other elements.

The valence electrons can be determined by the lewis dot structures. Lewis dot structures are the structures in which the valence electrons around the nucleus of an element are shown.

For the given compounds, only one compound do not follow octet rule which is

In the given compound, the octet of all the 3 fluorine atoms are complete but chlorine has 10 electrons around it which is not followed by octet rule.

b

explanation:

mitosis

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.