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.
Answer: I am actually studying about Stars, so I got you.
3. As the temperature of a star Increases, it's luminosity increases.
As the temperature of a star decreases, it's luminosity decreases.
4. Hot and Bright. The bigger the star, the hotter it gets is from what I learned.
The properties of a mineral depend on the kind of atoms of mineral being examined
Answer:
The answer is
<h2>5.0 g/cm³</h2>
Explanation:
The density of a substance can be found by using the formula
From the question
mass = 35 g
volume = 7 cm³
The density is
We have the final answer as
<h3>5.0 g/cm³</h3>
Hope this helps you
<span>When a large number of atoms of the same isotope are observed they will have a statistically consistent half life.
</span>An unstable nucleus contains a near excessive number of RNA chemical can spontaneously break apart into one or more nuclei all with a lighter state. #believe