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:
filtration is the process of using a filter to remove solids from liquids or gasses.
Example:
an example of this is tea.
Electron affinity for fluorine is than chlorine most likely , due to the electron repulsion that occur between the electron where n= 2 . the elements in the second period have such small electron clouds that electron repulsion is greater than that of the rest of the family.
The individual numbers which are present in chemical formula is subscript.
<h3>What is chemical formula?</h3>
Chemical formula of any compound of chemistry consist more than one atoms in it and gives idea about the number of atoms present in that compound.
Given chemical formula of glucose is C₆H₁₂O₆.
In the given chemical formula of glucose, number which shows the amount of carbon, hydrogen and oxygen are known as subscripts.
Hence, individual number are subscript.
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<h3>
Answer:</h3>
1.827 × 10²⁴ molecules H₂S
<h3>
General Formulas and Concepts:</h3>
<u>Math</u>
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Chemistry</u>
<u>Compounds</u>
- Writing Compounds
- Acids/Bases
<u>Atomic Structure</u>
- Reading a Periodic Table
- Using Dimensional Analysis
- Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
103.4 g H₂S (Sulfuric Acid)
<u>Step 2: Identify Conversions</u>
Avogadro's Number
Molar Mass of H - 1.01 g/mol
Molar Mass of S - 32.07 g/mol
Molar Mass of H₂S - 2(1.01) + 32.07 = 34.09 g/mol
<u>Step 3: Convert</u>
- Set up:
- Multiply:
<u>Step 4: Check</u>
<em>Follow sig fig rules and round. We are given 4 sig figs.</em>
1.82656 × 10²⁴ molecules H₂S ≈ 1.827 × 10²⁴ molecules H₂S
