Which action is a critical part of listening?
1 answer:
You might be interested in
Answer:
That iron atom is oxidized. It loses two electrons.
Explanation:
Compare the formula of an iron atom and an iron(II) ion:
- Iron atom:
;
- Iron(II) ion:
.
The superscript in the iron(II) ion is the only difference between the two formulas. This superscript indicates a charge of
on each ion. Atoms and ions contain protons. In many cases, they also contain electrons. Each proton carries a positive charge of
and each electron carries a charge of
. Atoms are neutral for they contain an equal number of protons and electrons.
Protons are located at the center of atoms inside the nuclei. They cannot be gained or lost in chemical reactions. However, electrons are outside the nuclei and can be gained or lost. When an atom loses one or more electrons, it will carry more positive charge than negative charge. It will becomes a positive ion. Conversely, when an atom gains one or more electrons, it becomes a negative ion.
An iron atom will need to lose two electrons to become a positive iron(II) ion
with a charge of
on each ion. That is:
.
- Oxidation is Losing one or more electrons;
- Reduction is Gaining one or more electrons.
This definition can be written as the acronym OILRIG. (Khan Academy.)
In this case, each iron atom loses two electrons. Therefore the iron atoms here are oxidized.
Rate equation for first order reaction is as follows:
Here, k is rate constant of the reaction, t is time of the reaction, is initial concentration and
is concentration at time t.
The rate constant of the reaction is .
(a) Let the initial concentration be 100, If 90% of the chemical is destroyed, the chemical present at time t will be 100-90=10, on putting the values,
Thus, time required to destroy 90% of the chemical is 23.03 days.
(b) Let the initial concentration be 100, If 99% of the chemical is destroyed, the chemical present at time t will be 100-99=1, on putting the values,
Thus, time required to destroy 99% of the chemical is 46.06 days.
(c) Let the initial concentration be 100, If 99.9% of the chemical is destroyed, the chemical present at time t will be 100-99.9=0.1, on putting the values,
Thus, time required to destroy 99.9% of the chemical is 69.09 days.