Answer:
Antoine Lavoisier and Johann Wolfang Döbereiner organized the elements based on properties such as how the elements reacts or whether they are solid or liquid.
Explanation:
The periodic table of the elements as we have it today was developed as a result of the work of several notable centuries who lived centuries apart, all of who made notable contributions to development of the modern periodic table in use today.
In 1789, Antoine Lavoisier, a French Chemist provided a definition of elemets which he defined as a substance whose smallest units cannot be broken down into a simpler substance. He further grouped the elements into two as metals and nonmetals.
In 1829, German physicist Johann Wolfang Döbereiner arranged elements in groups of three in increasing order of atomic weight and called them triads. His arrangement owasf elements into triads was based on his observation of similarities in physical and chemical properties of certain elements.
John Newlands, a British Chemist was the first to arrange the elements into a periodic table with increasing order of atomic masses.
In 1869, Russian chemist Dmitri Mendeleev developed a periodic table which provided a framework the modern periodic table. He arranged the elements according to their atomic weight, leaving gaps for elements that were yet to be discovered.
The modern periodic table arranges elements based on increasing atomic number.
Answer:
42 19 K→42 20 Ca+e−
Explanation:
Naturally-occurring potassium atoms have a weighted average atomic mass of 39.10 (as seen on most modern versions of the periodic table.) Each potassium atom contains 19 protons p+ and thus an average potassium atom contains about 39.10−19≈20 neutrons n0.
This particular isotope of potassium-42 contains 42 nucleons (i.e., protons and neutrons, combined;) Like other isotopes of potassium 19 out of these nucleons are protons; the rest 42−19=23 are therefore neutrons.
The pH of a 0.260 M solution of ascorbic acid is 0.585. Details about pH can be found below.
<h3>How to calculate pH?</h3>
The pH of a solution can be calculated using the following expression:
pH = - log {H+}
According to this question, ascorbic acid is a diprotic acid and posseses a concentration of 0.260M. The pH can be calculated as follows;
pH = - log {0.260}
pH = 0.585
Therefore, the pH of a 0.260 M solution of ascorbic acid is 0.585.
Learn more about pH at: brainly.com/question/15289741
#SPJ1
this is the answer is
Zn<span> + </span>HCl<span> = </span>ZnCl2<span> + </span>H2 <span> </span>
I believe that it is liquid.
