The atomic # and the mass #.
The chemist the count the number of particles (Atoms, Molecules or Formula Unit) in a given number of moles of a substance by using following relationship.
Moles = # of Particles / 6.022 × 10²³
Or,
# of Particles = Moles × 6.022 × 10²³
So, from above relation it is found that 1 mole of any substance contains exactly 6.022 × 10²³ particles. Greater the number of moles greater will be the number of particles.
Increasing the concentration of one or more reactants will often increase the rate of reaction. This occurs because a higher concentration of a reactant will lead to more collisions of that reactant in a specific time period.
Reaction rate increases with concentration, as described by the rate law and explained by collision theory. As reactant concentration increases, the frequency of collision increases. The rate of gaseous reactions increases with pressure, which is, in fact, equivalent to an increase in concentration of the gas.
Answer: The new volume of cake is 1.31 mL.
Explanation:
Given: 
= 0.20 mL, 
= ?, 
Formula used to calculate new volume is as follows.
Substitute the values into above formula as follows.
Thus, we can conclude that the new volume of cake is 1.31 mL.
Answer:
Titration
Explanation:
The best technique which can be used to determine the number of moles of the HCl in the sample is titration.
The given amount of HCl solution must be titrated with known concentration of the base like NaOH.
The volume of NaOH required must be noted also.
According to the reaction,
At equivalence point
Moles of 
= Moles of 
Considering:-
Moles of 
Thus, in this way, moles of HCl can be determined.
