Resistance of a material being scratched in known as: Hardness
Answer:
Mass= 2.77g
Explanation:
Applying
P=2.09atm, V= 1.13L, R= 0.082, T= 291K, Mm of N2= 28
PV=nRT
NB
Moles(n) = m/M
PV=m/M×RT
m= PVM/RT
Substitute and Simplify
m= (2.09×1.13×28)/(0.082×291)
m= 2.77g
Answer: 
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
The double displacement reaction in which one of the product is formed as a solid is called as precipitation reaction.
The balanced molecular equation is:
The increase in the number of atoms allows the strong positive charge of the nucleus to increase. Thus, due to the number of positive protons increasing in the nucleus, the positive charge increases. On the negatively charged electron cloud, the high positive charge of the nucleus has a strong tug.