FREE Introduction to Natural Science CLEP Question and Answers
What among the following signifies a chemical change?
Explanation:
> A chemical change is exemplified by a spoiled apple. One material changes into another during a chemical reaction. When an apple rots, a chemical process called oxidation takes place.
> When water sublimates, it transitions directly from the liquid phase of matter to the solid and gaseous phases of matter. This is not a chemical reaction; it is a phase transition.
> Since the salt and water can be separated once more by evaporating the water, the term "dissolution of salt in water" refers to a physical change.
> A physical alteration where the form but not the substance itself has altered is pulverized rock.
Of the data sets, which one could be represented as a pie chart?
Explanation:
In this scenario, a pie chart can show both the overall player count and the player count (or percentage) at each weight. For instance, it would be simple to infer from the data that 75% of the team weighs 250 pounds or more, 20% weighs 200 to 250 pounds, and just 5% weighs less than 200 pounds. To compare variables or sums that do not vary significantly, a bar or line chart would serve the other responses better.
Which sort of nuclear process involves the splitting of atomic nuclei into smaller nuclei?
Explanation:
> Atomic nuclei break into smaller nuclei during a nuclear process called fission. Gamma rays, a significant quantity of energy, and daughter products can all be released during nuclear fission. Both nuclear power plants and explosives use it.
> Fusion is a nuclear process in which two lighter atomic nuclei combine to generate a heavier nucleus, as in stars. Depending on the initial ingredients, this can either emit or absorb energy.
> Ionization is the process by which atoms acquire a positive or negative charge because the number of electrons does not equal the number of protons.
> Decay refers to an atomic nucleus spontaneously losing energy and producing ionizing particles and radiation.
Which of the following procedures separates materials using electrical charges?
Explanation:
Electrophoresis, commonly referred to as gel electrophoresis, is a technique for separating materials like protein, DNA, and RNA using electrical charges. Depending on the amount of electrical charge used. Measurement of visible light, near-ultraviolet, and near-infrared wavelengths is referred to as spectroscopic analysis.
Chromatography is the name given to a multitude of methods for separating chemical mixtures based on differences in the affinities of the constituents for a stationary phase, which is often a porous solid, and a mobile phase, which can either be a liquid or a gas. By rotating a mixture to create centripetal force, centrifugation separates mixtures by causing heavier particles to separate from lighter particles.
A hypothesis becomes a ____________ if it has been confirmed and accepted.
Explanation:
> A hypothesis turns into a theory if it has been confirmed and accepted. A widely accepted hypothesis is an explanation that has undergone extensive development and testing. A theory can be expected to predict test results and to explain evidence.
> In contrast to a scientific theory, which is a larger body of acknowledged information, principles, or correlations that may explain the fact, a fact is thought to be an objective and verifiable observation.
> Law is an explanation of things that always have the same result.
> Conclusion is more of a choice and may be supported by observation, facts, evidence, laws, or even convictions.
Energy measurements within a system are known as _________.
Explanation:
> Heat is the term for the energy levels present in a system.
> The average kinetic energy of the molecules in a substance is measured by its temperature. Higher temperatures correspond to molecules having more kinetic energy and moving more quickly.
> Entropy, which is connected to the second law of thermodynamics, is the quantity of energy no longer available for work.
> The study of how energy is transformed into heat and work in a system is known as thermodynamics.
Which of the following steps should be followed when performing a dissection in class?
Explanation:
Decaying specimens can be used during a dissection in class, however unidentified specimens are never allowed. Before handling, rinsing the specimen can help remove any extra preservative that might be unpleasant. It is always necessary to dispose of dangerous chemicals in accordance with district standards. It is wise to excuse students from the dissection if they have open sores on their hands that cannot be covered. Through open skin cracks, pathogens and harmful chemicals can enter the body.