Nursing Elites

1. What is the process of separating a mixture based on the different boiling points of its components called?

• A. Filtration
• B. Chromatography
• C. Distillation
• D. Centrifugation

Correct answer: C

Rationale: Distillation is the process of separating a mixture based on the different boiling points of its components. During distillation, the mixture is heated to vaporize the component with the lowest boiling point first. The vapor is then cooled and condensed back into a liquid, allowing for the collection of fractions with different boiling ranges. This technique is effective for separating components that have significantly different boiling points. Filtration (Choice A) is a method used to separate solids from liquids or gases using a filter medium. Chromatography (Choice B) is a technique used to separate components of a mixture based on their differential affinities to a stationary phase and a mobile phase. Centrifugation (Choice D) is a process of separating particles from a solution based on differences in size, shape, density, and viscosity by spinning the mixture at high speeds.

2. What type of bond is present in salt?

• A. Ionic
• B. Nonpolar covalent
• C. Polar covalent
• D. Peptide

Correct answer: A

Rationale: The correct answer is 'Ionic.' Ionic bonds are formed in salts through the transfer of electrons between atoms, leading to the attraction between positively and negatively charged ions. This results in a stable ionic compound, such as common table salt (sodium chloride). Nonpolar covalent, polar covalent, and peptide bonds are not typically found in salts. Nonpolar covalent bonds involve the equal sharing of electrons, polar covalent bonds involve unequal sharing of electrons, and peptide bonds are specific to proteins, not salts.

3. What happens to the kinetic energy of an object when its velocity is doubled?

• A. Kinetic energy remains the same
• B. Kinetic energy is halved
• C. Kinetic energy doubles
• D. Kinetic energy quadruples

Correct answer: C

Rationale: Kinetic energy is directly proportional to the square of the velocity of an object according to the kinetic energy formula (KE = 0.5 * m * v^2). When the velocity is doubled, the kinetic energy increases by a factor of four (2^2), which means it doubles. Therefore, when the velocity of an object is doubled, its kinetic energy also doubles. Choice A is incorrect because kinetic energy is not constant but dependent on velocity. Choice B is incorrect because halving the velocity would result in 1/4 of the original kinetic energy. Choice D is incorrect as quadrupling the kinetic energy would occur if the velocity is squared, not the kinetic energy.

4. What is the study of the geographical distribution of organisms and the factors that influence it known as?

• A. Paleontology (the study of fossils)
• B. Taxonomy (the classification of organisms)
• C. Biogeography
• D. Population genetics

Correct answer: C

Rationale: Biogeography is the scientific discipline that focuses on studying the geographical distribution of organisms and the factors that influence their patterns of distribution. This field investigates the reasons behind why species are located where they are, taking into account historical events, ecological interactions, and physical geography. Paleontology (option A) specifically deals with the study of fossils and the history of life on Earth, mainly focusing on extinct organisms. Taxonomy (option B) is the science that involves classifying and naming organisms based on their characteristics. Population genetics (option D) is concerned with the study of genetic variation and evolutionary processes within populations of organisms. Therefore, in the context of studying the distribution of organisms across space and time, biogeography is the most appropriate choice.

5. Which of the following best describes the relationship among density, volume, and mass?

• A. As volume increases, density decreases.
• B. As volume decreases, density increases.
• C. An object's mass does not affect its density.
• D. As volume decreases, mass increases.

Correct answer: B

Rationale: The correct answer is B: 'As volume decreases, density increases.' This is because density is defined as mass divided by volume. When volume decreases and mass remains constant, the ratio of mass to volume increases, leading to higher density. Choice A is incorrect because as volume increases, density typically remains constant or increases due to the mass also increasing. Choice C is incorrect because an object's density is directly influenced by its mass. Choice D is incorrect as decreasing volume does not lead to an increase in mass.

Similar Questions