Answer: The correct statement is (A new substance is formed and the process can usually NOT be undone.)
Explanation:
A chemical reaction is simply defined as the reaction between two or more elements in which a new substance is formed and the process can usually not be undone. Different types of chemical reaction includes:
-- combination reaction: this occurs when two or more reactants form a product. For example: In the burning of coal, It combines with oxygen to produce carbon dioxide. Also in the burning of wood, carbon dioxide is given off and ashes are formed. Because new substance is being formed, they often can't be undone. The ashes formed can't be changed back into wood. Other types of chemical reaction are listed below.
-- Decomposition reaction
-- Single displacement reaction
-- Double displacement reaction
-- combustion reaction
-- Redox reaction
For the product of a chemical reaction to be undone (reversed), it has to undergo another chemical process different from the one that produced it.
Answer:

Explanation:
Hello!
In this case, given this is an acid-base neutralization and we are considering a diprotic acid, we can write the following mole-mole relationship:

It means that the moles of acid can be computed given the volume and concentration of NaOH:

It means that the approximate molar mass of the acid is:

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The highest atom economy
2CO + O₂ ⇒ 2CO₂
<h3>Further explanation</h3>
Given
The reaction for the production of CO₂
Required
The highest atom economy
Solution
In reactions, there are sometimes unwanted products that can be said to be a by-product or a waste product. Meanwhile, the desired product can be said to be a useful product, which can be shown as the atom economy
of the reaction
the higher the atomic economy value of a reaction, the smaller the waste/ byproducts produced, so that less energy is wasted
The general formula:
Atom economy = (mass of useful product : mass of all reactants/products) x 100
<em>or
</em>
Atom economy = (total formula masses of useful product : total formula masses of all reactants/products) x 100
So a reaction that only produces one product will have the highest atomic value, namely the reaction in option C
Explanation:
What's Dis Suppose To Mean ?
In a dilute acid solution most if not all of the molecules will split into ions.
For example HCl is a strong acid and 100% of the molecules will split into
H+ & Cl-
in a weak acid solution only a portion of the molecules will turn into ions because the ionization percentage isn't as large. Which will essentially leave a high percentage of un-reacted molecules