The alkali metals are so reactive that they are never found in nature in elemental form. Although some of their ores are abundant, isolating them from their ores is somewhat difficult. For these reasons, the group 1 elements were unknown until the early 19th century, when Sir Humphry Davy first prepared sodium (Na) and potassium (K) by passing an electric current through molten alkalis. (The ashes produced by the combustion of wood are largely composed of potassium and sodium carbonate.) Lithium (Li) was discovered 10 years later when the Swedish chemist Johan Arfwedson was studying the composition of a new Brazilian mineral. Cesium (Cs) and rubidium (Rb) were not discovered until the 1860s, when Robert Bunsen conducted a systematic search for new elements. Known to chemistry students as the inventor of the Bunsen burner, Bunsen’s spectroscopic studies of ores showed sky blue and deep red emission lines that he attributed to two new elements, Cs and Rb, respectively. Francium (Fr) is found in only trace amounts in nature, so our knowledge of its chemistry is limited. All the isotopes of Fr have very short half-lives, in contrast to the other elements in group 1.
Ionic bonds are a metal and a non metal bond and a covalent bond is two no metals banded together.
Answer:
Easy my dude let me help you out
A.In
B.27
C.73
D.49
E.56
F.56
G.114
H.180
Also with protons and electrons they equal the same atomic number
From the calculation, the concentration in parts per billion is 6 ppb.
<h3>What is ppb?</h3>
The term ppb refers to the concentration of a substance in parts per billion. We obtain the ppb using the formula;
Mass of solute/ Mass of solution * 10^9
Now, 1L = 1000cm^3 = 1000 g
The concertation in ppb = 6 * 10^-6 g/1000 g * 10^9
= 6 ppb
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