A student used a pipette to add 25.0 cm of KOH of unknown concentration to a conical flask.
The student carried out a titration experiment to find the volume of 0.150 mol/dmº
H2SO4 needed to neutralise the KOH.
The student found that, on average, 17.20 cm of the H2SO4 solution was
required for neutralisation.

Calculate the concentration of the KOH solution.

The concentration of the KOH solution = 0.2064 M

Titration is a procedure for determining the concentration of a solution (analyte) by reacting with another solution whose known concentration (usually a standard solution) is called the titrant. Determination of the endpoint/equivalence point of the reaction can use indicators according to the appropriate pH range  

Acid-base titration formula  

Ma Va. na = Mb. Vb. nb  

Ma, Mb = acid base concentration  

Va, Vb = acid base volume  

na, nb = acid base valence  (number of ions H+/OH-)

a=H₂SO4(valence = 2, H₂SO4⇒2H⁺+SO₄²⁻, 2 ions H⁺)

b=KOH(valence = 1, KOH⇒K⁺+OH⁻, 1 ion OH⁻)

Ma = 0.15 M

Va = 17.2 cm³

Vb=25 cm³

The concentration of the KOH(Mb) :

answer: option (4) is the correct answer.

explanation:

areas which are at low altitudes and near the equator tend to receive direct sunlight from the sun. hence, heat energy or radiations from the sun make these areas warmer and they have warmest water.

whereas areas which are at high altitudes and away from the equator do no receive direct sunlight. hence, no direct contact from the sun makes these regions colder and thus, they have colder water.

thus, we can conclude that the statement areas at low latitudes near the equator have the warmest water because they receive the most direct sunlight best explains the relationship between an area's geography and the temperature of its surface water.

i think its 100.

hope this !