Final Review 1-30 Questions (Ref.; Study Guide 423)

A universal solvent is a type of solvent that has the ability to dissolve a wide range of substances. Water is often referred to as a universal solvent because it has the ability to dissolve many different types of molecules, including salts, sugars, acids, and bases. This is due to its unique molecular structure and polarity, which allows it to form hydrogen bonds with other molecules. As a result, water is able to dissolve a wide variety of substances, making it a universal solvent.

Protons are subatomic particles that have a positive charge and are located inside the nucleus of an atom. Neutrons, on the other hand, have no charge, while electrons have a negative charge and are found outside the nucleus. Valance electrons are electrons located in the outermost shell of an atom and are involved in chemical bonding. Therefore, the correct answer is proton.

Scientists use the word "precise" when they perform an experiment several times to get the "perfect measurement". This term refers to the level of accuracy and consistency in obtaining the same result repeatedly. By conducting multiple trials and achieving similar outcomes, scientists can determine the precise value or measurement of a particular variable in their experiment.

The metric unit used to measure "length" or "distance" is the meter. The meter is a fundamental unit of length in the International System of Units (SI). It is defined as the distance traveled by light in a vacuum in 1/299,792,458 of a second. The meter is widely used in scientific and everyday applications for measuring distances, such as the length of objects, distances between two points, or the height of buildings.

The curved line on the graduated cylinder is called the meniscus. It is important to have the meniscus at eye level in order to accurately measure the volume of liquid in the cylinder. The meniscus forms due to the surface tension of the liquid, causing it to curve slightly. By aligning the meniscus with the eye level, any parallax errors can be minimized, ensuring a more accurate measurement of volume.

The independent variable is the variable that the scientist purposely changes in an experiment. It is the variable that is manipulated or controlled by the researcher. In this case, it is the only variable that is intentionally altered during the experiment. It is also represented on the X axis or bottom axis on the graph, which further supports the idea that it is the independent variable.

A graduated cylinder is a scientific instrument used to measure the volume of liquids. It is a tall, cylindrical container with markings along its length, allowing for accurate measurement of the volume of a liquid. The markings on the graduated cylinder provide precise measurements in milliliters or liters. This instrument is commonly used in chemistry and biology experiments to measure the volume of liquids with high accuracy. It is designed to minimize errors and provide reliable results when determining the volume of a liquid.

An atom is the smallest piece of a nonliving particle of an element and is known as the building block of all matter. Atoms are composed of subatomic particles such as protons, neutrons, and electrons. They combine to form molecules, which in turn combine to form cells, elements, and ultimately all matter.

A compound is formed when two or more elements chemically combine. In a compound, the elements are bonded together in a fixed ratio and cannot be easily separated. This is different from a mixture, where the elements are physically combined and can be separated by physical means. An element, on the other hand, is a pure substance that cannot be broken down into simpler substances by chemical means. A molecule refers to the smallest unit of a compound or an element that retains its chemical properties.

The scientific method refers to the systematic approach that scientists follow to conduct experiments. It involves a series of steps, including making observations, formulating a hypothesis, designing and conducting experiments, collecting and analyzing data, and drawing conclusions. The scientific method ensures that experiments are conducted in a structured and logical manner, allowing scientists to test their hypotheses and make reliable and valid conclusions based on evidence.

Salinity refers to the total amount of dissolved salt in a water sample. It is a measure of the concentration of salt in the water and is usually expressed in parts per thousand (ppt) or as a percentage. Salinity is an important parameter in oceanography and can vary depending on factors such as evaporation, precipitation, and freshwater input. Therefore, salinity is the correct answer to the question about the total amount of dissolved salt in a water sample.

The neutron is a subatomic particle of an atom that has a neutral charge. It is located inside the atom, along with the positively charged protons and negatively charged electrons. Neutrons play a crucial role in determining the stability and properties of an atom, as they help to balance the positive charge of the protons in the nucleus. They also contribute to the mass of an atom, along with the protons.

A cell is the basic unit of structure of all living things and is the smallest piece of a living thing. Cells are the building blocks of life, responsible for carrying out all the necessary functions to maintain life. They are capable of reproducing, obtaining energy, and responding to their environment. Cells can be found in all living organisms, from single-celled organisms like bacteria to complex multicellular organisms like humans. Therefore, the answer to this question is cell.

An element is a pure substance that cannot be broken down into another substance physically or chemically. It consists of only one type of atom, such as gold or oxygen. Elements are the building blocks of all matter and are represented by unique symbols on the periodic table. Unlike compounds or molecules, elements cannot be further broken down or separated into simpler substances.

Heterogeneous mixtures are made up of different materials that can be easily separated. In the case of soil or trail mix, they contain different components such as rocks, sand, organic matter, nuts, and dried fruits. These components can be visually distinguished and separated using physical methods like filtering or picking out the different parts. Therefore, heterogeneous mixtures are the correct answer for this question.

Homogeneous mixtures cannot be separated easily and appear uniform throughout, just like Kool-aid or soap mixed in water. In a homogeneous mixture, the components are evenly distributed at a molecular level, making it difficult to distinguish the individual substances. This is in contrast to heterogeneous mixtures, where the components are not evenly distributed and can be easily separated. An example of a heterogeneous mixture would be a salad dressing, where oil and vinegar separate into distinct layers when left undisturbed.

A molecule is a combination of two or more atoms that are bonded together. It is the smallest part of a compound, meaning that it cannot be further divided without breaking the chemical bonds. In this context, atoms refer to the individual building blocks of matter, while cells and elements are not relevant to the definition of a compound.

Electrons are subatomic particles that carry a negative charge and are found in the orbits or energy levels of an atom. They are fundamental components of atoms and play a crucial role in chemical bonding and electricity. Protons, on the other hand, carry a positive charge, while neutrons have no charge. Quarks are elementary particles that make up protons and neutrons but are not directly involved in the location or charge of an atom's energy levels.

A spring scale is a scientific instrument used to measure force. It consists of a coiled spring that stretches or compresses in response to the force being applied. The amount of stretch or compression is directly proportional to the force being exerted. By measuring the displacement of the spring, the force can be determined. This makes the spring scale a reliable tool for measuring forces such as weight or tension.

A meter stick is a scientific instrument that is used to measure distance. It is a long, flat ruler that is typically one meter in length and is marked with centimeters and millimeters. The meter stick is commonly used in various scientific fields, such as physics and engineering, to accurately measure distances and lengths. It provides a reliable and standardized method for measuring objects and distances, making it an essential tool in scientific research and experimentation.

The metric unit used to measure mass is the gram.

Insoluble is the correct answer because it means "will not dissolve." The other options are not synonyms for "will not dissolve." Unsoluble is not a valid word, concrete refers to a building material, and suspension refers to a mixture where particles are suspended in a liquid but can still dissolve. Therefore, insoluble is the most appropriate word that means "will not dissolve."

The two subatomic particles located inside the nucleus of an atom are the proton and neutron. Protons have a positive charge and neutrons have no charge. Electrons, on the other hand, are located outside the nucleus in electron shells and have a negative charge. Therefore, the correct answer is proton and neutron.

H2O is a compound because it is made up of two different elements, hydrogen (H) and oxygen (O), chemically bonded together. In contrast, N2 is a diatomic molecule consisting of two nitrogen atoms bonded together, He is a noble gas consisting of a single helium atom, and Na2 is a diatomic molecule consisting of two sodium atoms bonded together.

Soluble is another word that means "when something dissolves." When a substance is soluble, it is capable of being dissolved in a liquid, usually water. This means that the substance can mix evenly with the liquid, forming a homogeneous solution. Soluble substances can be broken down into individual particles and dispersed throughout the solvent, resulting in a clear and transparent solution.

The metric unit used to measure volume or liquids is kiloliter. This unit is commonly used to measure large volumes of liquids, such as in industrial or commercial settings. It is equivalent to 1000 liters and is often used when dealing with large quantities of fluids.

H2 is the correct answer because it represents a single element, hydrogen. The other options, H2O, NaCl, and CO2, represent compounds made up of multiple elements.

The solute is the smaller amount of material being dissolved in a solution. In this case, the solute would be the powder of Kool-Aid or detergent, as they are being dissolved in a liquid solvent to form a solution.

A solution is a very well homogeneous mixture where the particles of the solute are evenly distributed and too small to settle out. In a solution, the solute is dissolved in the solvent, resulting in a mixture with the same properties throughout. Examples of solutions include Kool-aid, coffee, or tea, where the solute (such as sugar or coffee particles) is dissolved in the solvent (such as water) to create a uniform mixture.

The solute is the substance that is dissolved in a solvent to create a solution. In this case, the solute is the Kool-aid, which is the smaller amount of material used to dissolve in the solvent, which is water. Therefore, the solute is the larger amount of material used to dissolve the solute.