Explanation:
Brittleness is a characteristic that describes chalk. Its color and shape also describe the chalk. Any such characteristic of a material that you can observe without changing the substances that make up the material is a physical property
Gold is metallic, with a yellow colour when in a mass, but when finely divided it may be black, ruby, or purple. It is the most malleable and ductile metal
 
        
             
        
        
        
Explanation:
In a magnetic field, the radius of the charged particle is as follows.
              r = 
where,   m = mass,      v = velocity
               q = charge,    B = magnetic field
Therefore, q will be calculated as follows.
          q = 
             = 
             = 
             = 
             = +2e
Thus, we can conclude that the charge of the ionized atom is +2e.
 
        
             
        
        
        
Answer:
Option b. Decomposition
Followed by a reduction process using charcoal 
Explanation:
Lead can be obtained from lead nitrate by thermal decomposition of lead nitrate as shown below:
2Pb(NO3)2 —> 2PbO + 4NO2 + O2
The PbO obtained is reduced by charcoal(C) to obtain the metallic Pb as shown below:
2PbO + C —> Pb + CO2