Chemistry

Solutions and pH Chemistry

451 Questions

Solutions and pH chemistry focus on the acidity or alkalinity of various substances, from human urine to acidic soils. Questions involve titration calculations, molarity determination, and understanding mole fractions. This topic is a staple in the chemistry sections of state and national level competitive exams.

Calculating solution molarityMole fraction calculationpH value interpretationAcidic soils and pHTitration and neutralization

Solutions and pH Chemistry Questions

Multiple choice

Mole fraction can be defined as

  1. the number of moles of solute

  2. the number of moles of solvent

  3. the number of moles of the component divided by the total number of moles

  4. the total number of moles of solute and solvent
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ans : 3.

Multiple choice

The number of moles of solute dissolved in one kilogram of solvent is it's

  1. molarity

  2. molality

  3. density

  4. normality
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Molality is another common measurement of concentration. Molality is defined as the moles of solute divided by kilograms of solvent (the substance in which it is dissolved, like water).Molality is sometimes used in place of molarity at extreme temperatures because the volume can contract or expand.

Multiple choice

The molar mass of water is given as

  1. 15.15 g/mol

  2. 18.02 g/mol

  3. 17.01 g/mol

  4. 12.03 g/mol
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The molar mass of water (H2O) is calculated by adding the atomic mass of oxygen (approx 16.00) and two hydrogen atoms (approx 2 x 1.01), totaling 18.02 g/mol.

Multiple choice

In a true solution the size of solute particles is

  1. About 10-10 m

  2. 10 -9 -10 -7 m

  3. Greater than 10 -7 m

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In a true solution, the solute particles are very small, typically less than 1 nanometer (10^-9 m) in diameter, often around 10^-10 m.

Multiple choice

In humans, the pH of saliva varies from

  1. 8.0 to 10.0

  2. 7.5 to 8.0

  3. 7.5 to 9.0

  4. 6.7 to 7.2
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

 In humans, the pH of saliva varies from 6.7 to 7.2.The main enzyme in saliva (amylase, which breaks down starch) cannot function in an environment lower than a pH of 6.5. So, pH in this range is needed to promote mineral absorption and starch digestion.