Mass number is
protons + nuetrons
So,
7 + 8 = 15
——-
Atomic number is the number of protons
so,
7
Answer:
World War 3
Explanation:
People will go crazy wife or go to h*** in a become World War 3
Answer:
The chemical reaction is a Double Displacement
Explanation:
Balance the reaction of KOH + AlCl3 = KCl + Al(OH)3
Answer:
Most viscous to least viscous: 
Explanation:
For hydrocarbons, viscosity increases with increasing molar mass. Because increasing molar mass signifies increase in number of electrons in molecules.
We know that in non-polar hydrocarbons, only van der waal intermolecular force exists. Van der waal force is proportional to number of electrons in a molecule.
Therefore with increasing molar mass, van der waal force increases. hence molecules gets more tightly bind with each other resulting increase in viscosity.
Here molar mass order : 
Therefore viscosity order : 
It protects the nucleus and