The whitening toothpastes showed differences in their physical-chemical properties. All toothpastes promoted changes to the surface, probably by the use of a bleaching agent.
rate 1 of the reaction = k [A]²
rate 2 of the reaction = k [A/2]² = k[A]² /4
We can see that rate of the reaction will be 4 times less.
Here are some trends you should know.
Electronegativity increases as you go right and up along the periodic table.
So, (1) is wrong
Atomic mass increases as you go right and down along the periodic table.
So, (2) is wrong
Proton number or atomic number increases as you go right and down in the table.
So, (3) is correct
Metallic character increases as you go left and down along the periodic table.
So, (4) is wrong
Answer: There are 
moles 
present in 
particles.
Explanation:
According to the mole concept, 1 mole of a substance contains 
particles.
Hence, number of moles present in particles are calculated as follows.
No. of moles = 
mol
= mol
Thus, there are moles present in particles.
