Answer:
A combination reaction
Explanation:
The chemical reaction between ammonia and hydrochloric acid as shown below:
NH₃ + HCl → NH₄Cl
is a combination reaction.
In a combination reaction, two compounds combines together to give one compound.
A combination reaction is also known as a synthesis reaction.
A single product forms from tow or more reactants.
The driving force for such reaction is the large and negative heat of formation of the product.
The molar mass is the mass of all atoms in a molecule we first obtain the atomic weights from the individual elements in a periodic table then count the number of atoms and multiply it by the individual atomic masses
When an electron occupies an orbital of an atom singly, rather than an electron pair such electron is said to be an unpaired electron. Each atomic orbital of an atom specified by quantum numbers can contain a maximum of two electrons having opposite spins, electron pair.
The numbers of unpaired electrons are determined by the electronic configuration of an atom. The electronic configuration of calcium, 
is:
or ![[Ar]4s^{2}](https://tex.z-dn.net/?f=%5BAr%5D4s%5E%7B2%7D)
Since, from the electronic configuration it is clear that the number of electrons in valence orbital that is 
is 2 that means the electrons are paired up in the valence orbital so, there are no unpaired electrons present in .
Hence, the number of unpaired electrons in is 0.
Answer:
See Explanation
Explanation:
When a salt is dissolved in water, the solution could be acidic, basic or neutral depending on the nature of acid and base from which the salt was formed.
When a salt is formed from a strong acid and a weak base, the salt solution is acidic.
For instance, NH4Cl is a salt formed from NH3 which is a weak base and HCl which is a strong acid. The salt hydrolyses as follows;
NH4^+(aq) + H2O(l) ------> H3O^+(aq) + NH3(aq)
Hence an acidic solution is formed.
Answer: Sodium Nitrate solution is neutral.
Explanation: Sodium nitrate solution has strong bases and strong acids so it would have a neutral pH of 7.
