Answer:
A valence electron is an outer shell electron that is associated with an atom, and that can participate in the formation of a chemical bond. If the outer shell is not closed; in a single covalent bond. Both atoms in the bond contribute one valence electron in order to form a shared pair.
(Hope this helps) Sky
A ecosystem is SUSTAINABLE if it can continue to function over long periods of time.
Answer:
by changing the number of protons in the atom
Explanation:
Elements are defined by their number of protons. For example, an element with 1 proton is hydrogen, and an element with 2 protons is helium. Changing the number of neutrons or electrons in a preexisting element will not make a new element. Is is possible to create new elements, but it requires large amounts of heat and/or pressure.
<u>Answer:</u>
<em>The option a termed as precipitation reaction is incorrectly labelled.
</em>
<u>Explanation:</u>
The chemical reactions are classified based on the reactants used and products formed in a reaction. They are decomposition reaction, single displacement reaction, double displacement reaction, acid-base neutralisation reaction, precipitation reaction, combustion reaction, redox reaction and organic reaction.
Among these, the given options are labelled as precipitation and combustion reaction. The one which is labelled as combustion reaction is correct because combustion reactions occur in the presence of oxygen only and the products of combustion reaction should include water, oxygen or carbon and heat.
The other option which is labelled as precipitation reaction is incorrect because precipitation reaction occurs when an ionic substance will come out of a solution due to heating it or stirring it making the solubility of the ionic substance in a solution zero such that it will come out as solid and form a layer at the bottom of the solution.
But in this case all the products are in aqueous state, there is absence of any ionic substance in solid state, so the option which is labelled as precipitation reaction is incorrectly labelled.
