Answer:
Explanation:
The Ce metal has electronic configuration as follows
[Xe] 4f¹5d¹6s²
After losing 4 electrons , it gains noble gas configuration ,. So Ce ⁺⁴ is stable.
Eu has electronic configuration as follows
[ Xe ] 4 f ⁷6s²
[ Xe ] 4 f ⁷
Its outermost orbit contains 2 electrons so Eu²⁺ is stable. Its +3 oxidation state is also stable.
Ce⁺²
Answer:
0.185moles
Explanation:
Given parameters:
Volume of O₂ = 49.8L
Unknown:
Number of moles of sucrose required = ?
Solution:
We can assume that the reaction takes place at standard temperature and pressure.
From this, we can find the number of moles of oxygen that reacted and extrapolate to that of sucrose.
Chemical equation;
C₁₂H₂₂0₁₁ + 120₂ → 12CO₂ + 11H₂0
Number moles = 
at STP
Number of moles of oxygen gas = 
= 2.22moles
12 moles of oxygen gas combines with 1 mole of sucrose
2.22 moles of oxygen gas will combine with 
= 0.185moles
Mole - one of the most important concepts in chemistry - is a kind of link to go from the microworld of atoms and molecules in a normal macrocosm grams and kilograms.
In chemistry often have to consider large numbers of atoms and molecules. For fast and efficient calculation made using the weighing method. But it is necessary to know the weight of individual atoms and molecules. In order to identify the molecular weight must be added the weight of all atoms in the compound.
Ookay
1) T
2) T
3) F
Hope i helped :)
