Question 1

An example of this type of mixture is red blood cells in whole blood.

Accepted Answer

Red blood cells in whole blood form a suspension because the cells can be separated from the plasma by centrifugation, indicating that it's not a homogeneous mixture, solution, or colloidal dispersion. Whole blood does not qualify as a solvent itself.

Question 2

If the semipermeable membrane only allows the passage of water, what process will to occur?

Accepted Answer

E

Question 3

A student adds 0.250 L of 200 mM buffer stock solution to a volumetric flask and dilutes the stock to 2.0 L.What is the final concentration of the solution?

Accepted Answer

D

Question 4

Is the solution of MgCl₂ in water an electrolyte?

Accepted Answer

MgCl₂, when decoded from Unicode, represents MgCl2, which is magnesium chloride. Magnesium chloride dissolves in water to form magnesium and chloride ions, making the solution an electrolyte.

Question 5

A researcher needs 800 mL of a 25 mM phosphate buffer.The stock solution of the buffer is 100 mM.How much stock solution should be used to make the 25 mM phosphate buffer?

Accepted Answer

To prepare a diluted solution, use the formula C1V1 = C2V2. Here, C1 = 100 mM, V1 = ?, C2 = 25 mM, V2 = 800 mL. Solving for V1 gives V1 = (C2 * V2) / C1 = (25 mM * 800 mL) / 100 mM = 200 mL.

Question 6

We can predict whether a solute dissolves in a solvent with the rule "like dissolves like." This rule means that

Accepted Answer

The rule "like dissolves like" refers to the similarity in polarity between the solute and solvent. A polar solute will dissolve in a polar solvent, and a nonpolar solute will dissolve in a nonpolar solvent. This is because similar types of molecular interactions occur between molecules of the solute and the solvent when they have similar polarities.

Question 7

A technician adds 0.250 L of 200 mM buffer stock solution to a volumetric flask and dilutes the stock to 1.0 L.What is the final concentration of the solution?

Accepted Answer

The answer of A technician adds 0.250 L of 200...

Question 8

Drinking water from a well is discovered to have an arsenic concentration of 3.4 × 10^-4 g of arsenic per liter.Does this value exceed the permissible level of arsenic in drinking water of 10 ppb?

Accepted Answer

The permissible level of arsenic in drinking water is 10 ppb (parts per billion), which is equivalent to 10 × 10^-9 g/L or 1.0 × 10^-8 g/L. The concentration of arsenic in the well water is 3.4 × 10^-4 g/L, which is significantly higher than the permissible level, making choice B correct.

Question 9

Does gasoline, which is nonpolar, dissolve in water?

Accepted Answer

Gasoline is nonpolar and water is polar, and due to the principle "like dissolves like," nonpolar substances do not dissolve well in polar substances, hence gasoline does not dissolve in water because they do not have similar polarities.

Question 10

The function of a kidney is similar to which part of the diagram below?

Accepted Answer

The answer of The function of a kidney is similar...

Question 11

A patient is given 15 mL of a liquid pain reliever as a suspension containing 220 mg/5 mL of the pain reliever.How many milligrams of the pain reliever did the patient receive?

Accepted Answer

The patient received 660 mg of the pain reliever. This is calculated by using the ratio 220 mg/5 mL to find out how many milligrams are in 15 mL: (220 mg/5 mL) * 15 mL = 660 mg.

Question 12

How many moles of glucose are in 0.82 L of a 0.13 M glucose solution?

Accepted Answer

The number of moles of glucose can be calculated using the formula: moles = molarity × volume (in liters). Thus, 0.13 M × 0.82 L = 0.1066 mol, which rounds to 0.11 mol.

Question 13

Why do kidney stones form?

Accepted Answer

Kidney stones primarily form when calcium salt levels in the kidneys reach supersaturated levels and precipitate, leading to the formation of stones.

Question 14

Consider solutions A and B separated by a semipermeable membrane.Which diagram BEST illustrates what the volumes should look like after osmosis occurs?

Accepted Answer

The answer of Consider solutions A and B separated by...

Question 15

A _______ has components that are evenly distributed throughout the mixture.

Accepted Answer

A homogenous mixture has components that are evenly distributed throughout the mixture, meaning that any portion of the mixture has the same composition and properties as any other portion.

Question 16

Which of the following usually occurs when a molecule dissolves in water?

Accepted Answer

When a molecule dissolves in water, hydrogen bonds often form between the molecule and water. This is because water is a polar solvent, and its partial positive (hydrogen) and partial negative (oxygen) ends can interact with other polar molecules or ions, leading to the formation of hydrogen bonds. This interaction is crucial for the dissolution process but does not involve breaking or forming covalent bonds within the water or the solute molecule.

Question 17

A vial contains 5 mL of 1% aqueous lidocaine, a dental anesthetic.In this solution

Accepted Answer

Lidocaine is the solute because it is the substance dissolved in the solution, and water is the solvent because it is the substance that dissolves the solute, making up the majority of the solution.

Question 18

Which of the following is a heterogeneous mixture?

Accepted Answer

Oil and vinegar salad dressing is a heterogeneous mixture because it consists of two or more components that remain separate and can be visually distinguished. Unlike homogeneous mixtures, where the composition is uniform throughout, in a heterogeneous mixture like oil and vinegar salad dressing, the different components can be seen as separate layers.

Question 19

Glucose in the blood is a

Accepted Answer

Glucose in the blood is dissolved in water, forming a solution.

Question 20

A child is given 7.5 mL of a liquid pain reliever as a suspension containing 160 mg/5 mL of the pain reliever.How many milligrams of the pain reliever did the child receive?

Accepted Answer

The child received 240 mg of the pain reliever. This is calculated by setting up a proportion based on the concentration of the pain reliever (160 mg per 5 mL) and the amount given (7.5 mL): (160 mg / 5 mL) = (x mg / 7.5 mL), solving for x gives 240 mg.

Quiz 8: Mixtures, Solution Concentrations, and Diffusion