when pressure decreases what happens with the boiling point, it decreases, increases or stays the same? I read the book (the example used is water) were it says that if vapor pressure is less than the pressure pushing down on the surface the bubbles formed collapse; but when vapor pressure equals atmospheric pressure the bubbles get bigger and so boiling occurs. I havent been able to figured out the answer, can you please help me?
and please explain me why is that the answer.
Another question about boiling point, does salt water has a higher boiling point than water?
and the last one
How can I figured out which formula has the greates pH, for example if I get NaOH. How would I know this is the one that has the highest pH?
thanks in advance
1. So doesn't that mean that if the atmospheric pressure becomes less, then the vapor pressure must be less to boil, which means the boiling point will be _________?
2. I don't know quite how to answer this because I don't know your grade level. Let's try this.
Delta T = Kb m
where delta T is the boiling point elevation, Kb is the boiling point constant, and m is the molality of the solution. What this means is that if a non-volatile solute is dissolved in the water,(NaCl, sugar, etc), the boiling point will be higher.
3. The correct answer is that you can't unless the question is asked correctly. What this means is that given an acid such as HCl and a base such as NaOH you can correctly answer that NaOH will have the higher pH. Remember that numbers less than 7 are acid, 7 is neutral, and numbers greater than 7 are basic. Given NH3 (a WEAK base) and NaOH (a STRONG base) of equal concentrations, we can correctly answer that NaOH has a higher pH. But given a solution of Ba(OH)2 and Sr(OH)2 with no indication of the strength of each base, we can't say which has the higher pH.
1. When the pressure decreases, the boiling point decreases. This is because the boiling point is the temperature at which the vapor pressure of a liquid equals the pressure exerted on the liquid. If the pressure decreases, it requires less energy for the vapor pressure to equal the lower pressure, so the boiling point decreases.
To understand why this happens, we need to consider the process of boiling. When a liquid is heated, the molecules gain energy and move faster. At a certain temperature, the molecules have enough energy to overcome the attractive forces between them and escape into the gas phase, forming bubbles. These bubbles rise to the surface and burst, releasing the vapor.
The pressure on the liquid determines how tightly the gas molecules can be packed together. When the pressure is higher, the gas molecules are more densely packed, and it takes more energy for the liquid molecules to form bubbles and escape into the gas phase. Therefore, the boiling point is higher.
On the other hand, when the pressure is lower, there are fewer gas molecules for the liquid molecules to push against, and it takes less energy for the liquid molecules to become vapor and escape into the gas phase. Therefore, the boiling point decreases.
2. Saltwater has a higher boiling point than pure water. Adding salt to water increases the boiling point because the presence of solute particles disrupts the attractive forces between the water molecules. This disruption requires more energy (heat) to break the intermolecular bonds and convert the liquid into vapor, thus raising the boiling point.
In other words, water molecules in saltwater are surrounded by salt ions, which create an additional attractive force and make it harder for the water molecules to escape into the gas phase. As a result, the boiling point of saltwater is higher compared to pure water.
3. pH is a measure of the concentration of hydrogen ions (H+) in a solution, which indicates the acidity or basicity of the solution. A higher pH value indicates a lower concentration of H+ ions, meaning it is more basic.
To determine which formula has the highest pH, you need to consider the strength of the acid or base. Strong acids and bases completely dissociate in water, meaning they fully release H+ or OH- ions. Weak acids and bases, on the other hand, only partially dissociate.
In the example you provided, NaOH is a strong base, while HCl is a strong acid. Since pH is determined by the concentration of H+ ions, a strong base like NaOH, which releases OH- ions, will have a higher pH than a strong acid like HCl, which releases H+ ions. Therefore, NaOH has the higher pH.
However, it is important to note that without information about the strength of each acid or base or their concentrations, it is not possible to compare and determine which formula has the highest pH. The pH depends on the specific characteristics of each acid or base in the given scenario.