Answer:
division of atoms are neither created nor destroyed therefore atoms can only be rearranged
<span>Associating the need of surgeon in practice , we write a software of human body biocycle law . this software can provide a science reliance in the time selection of surgical operation plan to the main surgeon
(just an example^)</span>
Lar mass of Ca<span> = 40.08 </span>grams/mole 77.4 g Ca<span> * ( 1 </span>mole Ca<span>/ 40.08 ... n = m / M 1mol </span>Ca<span>weights 40 gmol-1 n = 77,4 / 40 = 1.93 </span>mol<span>.</span>
Dimitri Mendeleev was the first to put elements together on a table. He knew there were elements missing but he noticed a trend in some of the elements known at the time. Sodium, Lithium and other alkali metals all have the same properties so he put them under the same column and created other columns with similar attributes (Halogens, Noble gases, Alkaline earth metals). Over the years, new elements were discovered and put into the rough outline that Mendeleev created.
I hope that is about what you wanted.
Answer:
There are 6.022 × 10 23 O atoms in a mole of O atoms. There are 6.022 × 10 23 O 2 molecules in a mole of . Since you have 2 oxygen atoms in one molecule, there are 2 × 6.022 × 10 23 O atoms in a mole of . A 'mole' is not short for a 'molecule
Explanation: