You have to use Avogadro's number which is 6.02x10^23. The units of Avogadro's number is molecules/mole so you divide the number of molecules by Avogadro's number which will give you the number of moles.
(2.0x10^22 molecules)/(6.02x10^23 molecules/mole)=0.033 moles
Answer:
The bromine molecule, Br2 will likely react with Sr in a similar way to chlorine molecule, Cl2.
Explanation:
Chlorine belongs to group 7 of the periodic table. Elements in this group are known as halogens. Its molecule has the formula Cl2. The next element in the group after chlorine is bromine. Its molecule has a formula Br2. It has similar properties as chlorine, therefore, it would react with Strontium in a similar way to chlorine.
Elements belonging to the same group of the periodic the table have similar chemical properties as they contain the same number of valence electrons. Chlorine and Bromine both belong to group 7 of the periodic table and each have seven valence electrons. They both react with metals to form salts even though reaction with chlorine is more vigorous as it is more reactive than bromine. They both form negatively-charged ions with a charge of -1.
Reaction of Strontium with the halogens:
With chlorine: Sr + Cl2 ---> SrCl2
With bromine: Sr + Br2 ---> SrBr2
The salts formed are both crystalline salts with high melting and boiling points.
Answer:
In a chemical change, the atoms in the reactants rearrange themselves and bond together differently to form one or more new products with different characteristics than the reactants. When a new substance is formed, the change is called a chemical change.
Explanation:
<span>Divide the number of grams present in the sample by copper's gram atomic weight to find the number of gram atomic weights present. Then multiply that result by Avogadro's Number: 6.022137 x 10^23 atoms/gram atomic weight.1,200 g/(63.54 g/gram atomic weight) ? 18.885741 gram-atomic weights. Hope this helps. </span>
