<span>Avogadro's number
represents the number of units in one mole of any substance. This has the value
of 6.022 x 10^23 units / mole. This number can be used to convert the number of
atoms or molecules into number of moles. We calculate as follows:
0.340 mol Br2 ( </span>6.022 x 10^23 molecules / mol ) = 2.05 x 10^23 molecules
Answer:
B
Explanation:
Trust me I've had problems like these
Answer:
the advantages of modern periodic tables are given below and explained.
- position of hydrogen:since hydrogen has the least atomic number i.e 1 ,it is kept in group 1 of modern periodic table, but still controversial due to its. dual characteristics since it shows the characteristics of borh group 1 and group 17.
- position of isotopes :isotopes are element having the same atomic number but different atomic weight . Without any doubt all isotopes of one element and kept in one place.
- position of lanthanide and acnitinides: element of Lanthanides series and element of Actinides series are kept below the main block of the periodic table as they have different properties from other elements.
- correction of periodic law: some elements do not obey mendeleev periodic law , but when they are arranged according to atomic number they obey the modern periodic law.
- position of alkali metals and coinage metals : in modern periodic table , alkali metal are kept in group IA and coinage metals are in group.
hope this helped you☺️
any confusion then comment it and let me know.
actually as I say these points say that the modern periodic table is better than mendeleev periodic table so, don't get confused.
Answer
The empirical formula is CrO₂Cl₂
Explanation:
Empirical formula is the simplest whole number ratio of an atom present in a compound.
The compound contain, Chromium=33.6%
Chlorine=45.8%
Oxygen=20.6%
And the molar mass of Chromium(Cr)=51.996 g mol.
Chlorine containing molar mass (Cl)= 35.45 g mol.
Oxygen containing molar mass (O)=15.999 g mol.
Step-1
Then,we will get,
Cr=
mol
Cl= 
mol.
O=
mol.
Step-2
Divide the mole value with the smallest number of mole, we will get,
Cr=
Cl=
O=
Then, the empirical formula of the compound is CrO₂Cl₂ (Chromyl chloride)
Answer:
Explanation:
Filtration followed by evaporation:
To separate the mixture of sand and sugar, it is best to use the separation technique of filtration then evaporation.
Pour the water into the mixture. The sugar will dissolve with time in the water. Sand is made up of quartz and does not dissolve in water.
After the dissolution, filter the solution to separate the sand using a filter paper.
Dry the sand thereafter then proceed to evaporate the sugar with water solution. Evaporation will turn water into vapor and the sugar crystals will be left behind.
