Answer:
The answer is: Applied Chemistry
Explanation:
Apllied Chemistry is a branch of Chemistry that deals with the application and use of Chemistry principles and theories to answer a specific question or solve real world problems. It is aimed at taking Chemistry knowlege from the classroom to the real world. In this example, Marie noticed that a problem had arisen, and that is corrosion of metals, and she set out to apply the principles of Chemistry to make a paint formulation that prevvents corrosion, not just on paper with a bunch of formulas and calculations, but translated into a real life substance. On the other hand, pure Chemistry is the theoretical aspect of Chemistry, where the result of the researches are purely for knowlege and not for real world application.
I think it would be penicillin as it saved many lives in its time and ours.
Answer : The balanced equation is,

Explanation :
According to the Bronsted Lowry concept, Bronsted Lowry-acid is a substance that donates one or more hydrogen ion in a reaction and Bronsted Lowry-base is a substance that accepts one or more hydrogen ion in a reaction.
The balanced chemical reaction will be,

In this reaction, hydrofluoric acid is act as a Bronsted Lowry-acid because it donate one hydrogen ion to
and
is act as a Bronsted Lowry-base because it accept one hydrogen ion from
.
Answer:
11 electrons
Explanation:
The atomic number of sodium is 11. This tells us that sodium has 11 protons and because it is neutral it has 11 electrons. The mass number of an element tells us the number of protons AND neutrons in an atom (the two particles that have a measurable mass).
Explanation:
<u>Photovoltaic means electricity from light</u>
photo = <em>light </em> voltaic = <em>electricity</em><em> </em>
<u>SUNLIGHT</u> is the answer
Hope this is correct
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