L1 - Solutions - PP

Question 1

The solute

Answer 1

Is the substance which is dissolved

Question 2

The solvent

Answer 2

Is the substance in which the solute is dissolved

Question 3

Dilute solutions

Answer 3

Amount of solute is small compared to solvent

Question 4

Concentrated solutions:

Answer 4

Amount of solute is larhe compared to solvent

Question 5

Saturated solutions:

Answer 5

No more solute can be dissolved by the solvent in the presence of excess solute

Question 6

Density:

Answer 6

Mass (m) per unit volume (V). Symbole of density is “p”

Question 7

Isotonic solution;

Answer 7

A solution with the same osmotic pressure as blood, such as 0,9 percent NaCl, is an isotonic solution.

Question 8

Hypotonic solution

Answer 8

In a hypotonic solution, lower solute concentration than blood., water flows into the red blood cells which eventually burst (hemolysis)

Question 9

Hypertonic solution

Answer 9

In a hypertonic solution, higher solute concentration than blood, water flows from the red cell which shrinks (crenation).

Question 10

Crystalloids

Answer 10

Crystalloids are solid solutes which form true solutions, can pass through filters and animal membranes, can be crystallized from solutions.

Question 11

Suspensions

Answer 11

Suspensions are solid solutes which do not dissolve and are so heavy that they settle out.

Question 12

Colloids

Answer 12

Colloids are solid solutes, of a size in between crystalloids and suspension, which do not dissolve as crystalloids, but which are light enough so that they don’t settle down. May pass through filters but not animal membranes. Cannot be crystallized from solution.

Question 13

Sol

Answer 13

Sol is a liquid colloidal solution; gel is a solid colloidal solution.

Question 14

Colloid osmotic pressure;

Answer 14

Colloid osmotic pressure is the osmotic pressure which occurs as the result of the presence of a colloidal (impermeable) on one side of two compartment system separated by a semipermeable membrane, such as in the blood capillaries.

Question 15

True solutions:

Answer 15

Is a homogenous mixture of two or more substances at the molceular level. The components of a solution are known as the solute and the solvent.

Question 16

Arrhenius theory:

Answer 16

Arrhenius theory: An acid produces H+ in water solution;

A base produces OH- in water solution.

Question 17

Bronsted-Lowery theory:

Answer 17

The Bronsted-Lowery theory is the most prevalent of the 3 theories in organic chemistry.

• An acid is a proton donor.
• A base is a proton acceptor.
• Bases have conjugate acids.
• Acids have conjugate bases.
• The conjugate base is the remaining particle of the acid after a proton is released.

Question 18

Lewis theory:

Answer 18

Lewis theory: An acid is an electron pair acceptor; a base is an electron pair donor.

Question 19

Kw:

Answer 19

Kw – Ionic product for water.

Kw = [H+] [OHˉ] = 1∙10^-14

Question 20

Litmus color change:

Answer 20

Litmus changes color from red to blue as the pH of a solution increases from pH 6 to pH 8.

Question 21

Phenolphthalein color change:

Answer 21

Phenolphthalein goes from a colorless form to red as the pH of solution increases from pH 8 to pH 10.

Question 22

When are strong acids and bases are completely ionized?

Answer 22

Strong acids and bases are completely ionized in dilute aqueous solutions. Other acids and bases, because they ionize incompletely in water (often to the extent of only a few percent), are called weak acids and bases.

Question 23

Equivalence point of a titration:

Answer 23

Equivalence point of a titration is where the two substances were mixed in exactly equation proportions. Obviously there is need to choose an indicator which changes.

Question 24

The end point:

Answer 24

The end point is the point at which the titration is stopped.

Question 25

When will you not use an indicator?

Answer 25

One would never titrate a weak acid and a weak base in the presence of an indicator.