Answer:
Below are some patterns in the charge for elements in each group.
Group 1 elements : 1 valence electron and form ions with charge +1
Group 2 elements : 2 valence electrons and form ions with charge + 2
Group 3 elements : 3 valence electrons and form ions with charge + 3(there are some exceptions as well)
Elements in groups 4 and 5 are unpredictable also the D block elements consist of multiple oxidation states..
Group 6 elements : 6 valence electrons, form ions with charge -2
Group 7 elements: 7 valence electrons, form ions with charge -1
The octet rule is being followed, the elements form either ionic bond or covalent bond to fulfill it.
eg: when a K atom forms a K+ ion, the ion has the same electron configuration as the noble gas Ar (argon).
When an O atom gains 2 electrons to form the O²⁻ ion, the ion has the same electron configuration as the noble gas Ne (neon).
Note: Boron (B) is in Group 3 but doesn't form ions.
Answer:


Explanation:
NO is limit reactant so:
1÷7×46=6.57 grams of NO2 will form
Answer:
2.1 moles of water formed.
Explanation:
Given data:
Moles of water formed = ?
Moles of Ni(OH) = 4.20 mol
Solution:
Chemical equation:
2Ni(OH) → Ni₂O + H₂O
Now we will compare the moles of Ni(OH) with water.
Ni(OH) : H₂O
2 : 1
4.20 : 1/2×4.20 = 2.1 mol
2.1 moles of water formed.
1) (Hvap)(moles of water)=236.9783574kJ
(40.67)(105/18.02)
2) (change in temperature)(mass)(Cliquid)=43.9345172kJ
(100)(105/18.02)(75.4)/1000
3) (Hfus)(moles of water)=35.01942286kJ
(6.01)(105/18.02)
4) (change in temperature)(mass)(Csolid)=3.181465039kJ
(15)(105/18.02)(36.4)/1000
Total released=319.1137625kJ
It should be the third one. "Science deals with facts, pseudoscience deals with theories"