Answer is: <span>volume of the acid is 0,075 L.
</span>Chemical reaction: KOH + HCl → KCl + H₂O.
V(KOH) = 30 mL · 0,001 L/mL = 0,3 L.
c(KOH) = 0,5 M = 0,5 mol/L.
c(HCl) = 2 M = 2 mol/L.
V(HCl) = ?
From chemical reaction n(KOH) : n(HCl) = 1 : 1.
n(KOH) = n(HCl).
c(KOH) · V(KOH) = c(HCl) · V(HCl).
0,5M · 0,3 L = 2M · V(HCl).
V(HCl) = 0,075 L.
To the OH- from the ztrong base to form water and salt
Answer: Option (c) is the correct answer.
Explanation:
When an acid or base is added to a solution then any resistance by the solution in changing the pH of the solution is known as a buffer.
This is because a buffer has the ability to not get affected by the addition of small amounts of an acid or a base. As a result, it helps in maintaining the pH of the solution.
In the give case, when we add the HCl then more number of protons will dissociate. This causes the acetate to react with the protons and leads to the formation of acetic acid.
We know that acetic acid is a weak acid and it dissociates partially or feebly. Therefore, no change in pH will take place.
Thus, we can conclude that equation 
represents the chemical reaction that accounts for the fact that acid was added but there was no detectable change in pH.
Energy is required to change the phase of a substance, such as the energy to break the bonds between molecules in a block of ice so it may melt.
During a phase change energy my be added or subtracted from a system, but the temperature will not change. The temperature will change only when the phase change has completed. No temperature change occurs from heat transfer if ice melts and becomes liquid water (i.e., during a phase change). For example, consider water dripping from icicles melting on a roof warmed by the Sun. Conversely, water freezes in an ice tray cooled by lower-temperature surroundings. Energy is required to melt a solid because the cohesive bonds between the molecules in the solid must be broken apart so that the molecules can move around at comparable kinetic energies; thus, there is no rise in temperature.
Explanation:
Sublimation is defined as a process in which solid state of a substance directly changes into vapor or gaseous state without undergoing liquid phase.
For example, naphthalene balls show sublimation at room temperature.
As this process does not cause any change in chemical composition of a substance. Hence, it is known as a physical process.
Similarly, when 
sublimes readily at 
. This shows change in physical state of carbon dioxide is taking place, i.e, from solid to gaseous phase.
Thus, we can conclude that when sublimes readily at then it means physical properties are usually associated with a compound that undergoes this kind of change.
