Answer
Avogadro's number: One mole of any substance contains 6.022×10²³ molecules
Explanation
While finding the number of moles of oxygen molecules present in 3.65 moles of Na2SO4 the conversion factor used would be Avodagro's number, which is
One mole of any substance contains 6.022×10²³ molecules.
Answer:
1.
A= <u>sum</u><u>(</u><u>mass</u><u>*</u><u>percent</u><u> </u><u>abundance</u><u>)</u>
M 100
=(23.985*78.70)+(24.946*10.13)+(25.983*11.17)/100
= 24.3
2. The element is Magnesium.
3. 2412Mg,2512Mg and 2612Mg
Answer : The initial temperature of system 2 is, 
Explanation :
In this problem we assumed that the total energy of the combined systems remains constant.
The mass remains same.
where,
= heat capacity of system 1 = 19.9 J/mole.K
= heat capacity of system 2 = 28.2 J/mole.K
= final temperature of system = 
= initial temperature of system 1 = 
= initial temperature of system 2 = ?
Now put all the given values in the above formula, we get
Therefore, the initial temperature of system 2 is,
