Lithium, sodium, potassium, rubidium, cesium, and francium
        
             
        
        
        
Correct answer is option E. <span>It is a redox reaction in which Zn is oxidized at the anode, and V is reduced at the cathode.
Reason:
In above reaction, the oxidation state of VO3- is +5, while that of VO2 is +4. Thus there is reduction of V from +5 to +4
In case of Zn, oxidation state of Zn is increased from 0 to +2, Thus process is referred as oxidation. </span>
        
             
        
        
        
Answer:
B) number of electrons 
Explanation:
The two species: 
           K+   and Cl- have the same number of electrons. 
A neutral atom of K has 19 electrons 
A neutral atom of Cl has 17 electrons 
Now, 
  To form K+, K will have to lose an electron and then the number of electrons becomes 18 
To form Cl-, Cl will have to gain an electrons and then the number of electrons becomes 18 
So, therefore, the number of electrons on both species is 18
 
        
             
        
        
        
40.0 g ( 1 mole ) --------------- 6.02x10²³ molecules
      ? ? --------------------------- 2.90x10²² molecules
mass = 2.90x10²² * 40.0 /  6.02x10²³
mass = 1.16x10²⁴ / 6.02x10²³
mass = 1.9269 g
hope this helps!