Answer:Hence, the bond length in HCl is 125 pm.
Explanation:
Bond length : It is an average distance between the nuclei of two bonded atoms in a molecule.
Also given that bond length is the distance between the centers of two bonded atoms. on the potential energy curve, the bond length is the inter-nuclear distance between the two atoms when the potential energy of the system reaches its lowest value. Beyond this if atoms come closer to each other then their will be repulsion between them.
So, the bond length between the Hydrogen and Chlorine atom in HCl molecule is :

Hence, the bond length in HCl is 125 pm.
No. of moles in 134g of Mg, n=134/24 =5.58 moles
No. of atoms = n* Avogadro number
= 5.58 X 6.022 X 10^23
=33.60 X 10^23 atoms
The one after metamorphic rock is melting.
Answer:

------->
+ 

Explanation:
In equation 1, equating the mass number (A) on both sides.
A = 235 + 1 = A + 94 + 3*1
236 = A + 94 + 3
A = 236 - 94 = 3
A = 139
Equate the atomic numbers on both sides
92 + 0 = Z + 36 + 3*0
92 = Z + 36
Z = 92 - 36
Z = 56
In reaction 2, equating the mass number on both sides
235 + 1 = A + 143 + 3 *1
236 = A + 143 + 3
236 = Z + 146
Z = 90
Equatoing the atomic number of both sides
92 + 0 = Z + 54 + 3*0
92 = Z + 54
Z = 92 - 54
Z = 38.