Answer:
1.55 x 10²⁴ formula units
Explanation:
Given parameters:
Number of moles of CaCl₂ = 2.58moles
Unknown:
Formula units in the compound = ?
Solution:
To solve this problem, we must understand that;
1 mole of a substance contains 6.02 x 10²³ formula units
2.58 moles will contain 2.58 x 6.02 x 10²³ formula units
= 1.55 x 10²⁴ formula units
Explanation: Electron shielding could be defined as the reduction or mitigation in the effective cloud due to the differences in the attractive force of the nucleus on the electrons of an atom. Electron shielding explains the protection from attractive forces afforded to the outer electrons by their inner compatriot.
In Nitrogen, there are 3 2p electrons in the 2p sub-level which are shielded by 4 inner electrons; 2 in the 1s level and 2 in the 2s level. Therefore, the electrons in the 2p sub-level enjoy the greatest shielding from the attractive force of the nucleus due to the shield afforded to the valence electrons by the 4 inner electrons .
Answer:
43.05 moles of Al needed to react with 28.7 moles of FeO.
Explanation:
Given data:
Moles of FeO = 28.7 mol
Moles of Al needed to react with FeO = ?
Solution:
Chemical equation:
2Al + 3FeO → 3Fe + Al₂O₃
Now we will compare the moles of Al with FeO.
FeO : Al
2 : 3
28.7 : 3/2×28.7 = 43.05 mol
Thus 43.05 moles of Al needed to react with 28.7 moles of FeO.