Evaporation occurs when water molecules on the surface gain enough energy to enter the atmosphere. However, stronger intermolecular forces between water molecules cause them to be strongly attracted to each other and to tend to stay in the liquid phase. When the temperature is raised (when heat is applied), more molecules gain the energy needed to escape these intermolecular forces and go into the vapor phase.
Therefore the best answer is D.
The answer is <span>C. The mixture is made up of different consistencies.
The main difference between a heterogeneous and a homogeneous mixture is that the heterogeneous mixture is </span><span>made up of different consistencies that are not evenly mixed throughout. For example, the homogeneous mixture is milk while milk with cereals is the heterogeneous mixture.</span>
Answer:
24.309
Explanation:
mass×percentage+.. = average amu
23.985×78.7/100+24.986×10.13/100+25.983×11.17/100
to three decimal places
=24.309
Answer:
The pH and pOH of a 2.2*10⁻³ HBr solution is 2.66 and 11.34 respectively.
Explanation:
pH - short for hydrogen potential - is a measure of the acidity or alkalinity of a solution. So the pH is a parameter that indicates the concentration of hydrogen ions [H]⁺ that exist in a solution.
The pH is expressed as the negative base 10 logarithm of the hydrogen ion concentration. This is represented by:
pH= - log [H⁺]
pH is measured on a scale of 0 to 14. On this scale, a pH value of 7 is neutral, which means that the substance or solution is neither acidic nor alkaline. A pH value of less than 7 means that it is more acidic, and a pH value of more than 7 means that it is more alkaline.
HBr is a strong acid. Then, in aqueous solution it will be totally dissociated. So the proton concentration is equal to the initial concentration of acid:
[H⁺]= [HBr]= 2.2*10⁻³ M
So:
pH= - log (2.2*10⁻³)
pH= 2.66
On the other hand, pOH is a measure of the concentration of hydroxyl ions in a solution. The sum of pH and pOH equals 14:
pH + pOH= 14
2.66 + pOH= 14
pOH= 14 - 2.66
pOH= 11.34
<u><em>The pH and pOH of a 2.2*10⁻³ HBr solution is 2.66 and 11.34 respectively.</em></u>
