Answer:
- <em>He realized that some elements had not been discovered.</em>
Explanation:
Some scientists that tried to arrange the list of elements known before Mendeleev include Antoine Lavoisier, Johann Döbereiner, Alexandre Béguyer de Chancourtois, John Newlands, and Julius Lothar Meyer.
<em>Dimitri Mendeleev</em> was so succesful that he is recognized as the most important in such work.
Mendeleev by writing the properties of the elements on cards elaborated by him, and "playing" trying to order them, realized that, some properties regularly (periodically) repeated.
The elements were sorted in increasing atomic weight (which is not the actual order in the periodic table), but when an element did not meet the pattern discovered, he moved it to a position were its properties fitted.
The amazing creativity of Mendeleev led him to leave blanks for what he thought were places that should be occupied by elements yet undiscovered. More amazing is that he was able to predict the properties of some of those elements.
When years after some of the elements were discovered, the genius of Mendeleev was proven because the "new" elements had the properties predicted by him.
The number of amino acids that will be in the polypeptide chain produced by the normal DNA or MRNA sequence is usually 30 amino acids. Although the number of amino acids depends on the function of the generated DNA or RNA. The types of amino acids also differ depending on the function.
Answer:1)1.99 M
Explanation:
Molarity is given as = moles solute/Liter solution
The solute which is LiOH is already given in moles as 1.495 moles
Given that solution is 750 mL, we convert to liters.
Liters of the solution= mL of the solution x (1 L/1000 mL)
750 mL x (1 L/1000 mL)
0.75 L
Molarity = moles solute/Liter solution
Molarity = 1.495 moles of LiOH/0.75 L of solution
Molarity = 1.99M
The molarity of this solution is 1.99M (moles per liter).
A. Identify the properties as either a physical or chemical property. (first 3 are chemical, last is physical)
Answer:
B. Non-metals
Explanation:
The element with the atomic number of 17 is Cl.
Chlorine belongs to the group 7 in the periodic table. It is a non metal.
Correct option: B. Non-metals
