Answer:
chemical change because a different solid substance is formed.
Answer:
The answer to the question is A. :)
Explanation:
Atom are electrically neutral because in an atom the number of positively charged protons is exactly equal to the number of negatively charged electrons....

Answer : The correct option is, (B) bent, 2, and 
Explanation :
Formula used :
![\text{Number of electron pair}=\frac{1}{2}[V+N-C+A]](https://tex.z-dn.net/?f=%5Ctext%7BNumber%20of%20electron%20pair%7D%3D%5Cfrac%7B1%7D%7B2%7D%5BV%2BN-C%2BA%5D)
where,
V = number of valence electrons present in central atom
N = number of monovalent atoms bonded to central atom
C = charge of cation
A = charge of anion
The given molecule is, 
![\text{Number of electrons}=\frac{1}{2}\times [5+2+1]=4](https://tex.z-dn.net/?f=%5Ctext%7BNumber%20of%20electrons%7D%3D%5Cfrac%7B1%7D%7B2%7D%5Ctimes%20%5B5%2B2%2B1%5D%3D4)
Number of bond pair = 2
Number of lone pair = 2
The total number of electron pair are 4 that means the hybridization will be
and the electronic geometry of the molecule will be tetrahedral.
But as there are 2 atoms around the central oxygen atom, the third and fourth position will be occupied by lone pair of electrons. The repulsion between lone and bond pair of electrons is more and hence the molecular geometry will be bent or angular.
Hence, the correct option is, (B) bent, 2, and 
the second statement is the correct one quarks are needed to balance charges in all subatomic particles such as neutrons, protons and electrons