Biology 1 - Chapter 2 Vocab Quiz A

pH is the measure of hydrogen ions (H+) in a solution. It indicates the acidity or alkalinity of a solution on a scale of 0 to 14, with 0 being highly acidic, 7 being neutral, and 14 being highly alkaline. The pH scale is logarithmic, meaning that each unit represents a tenfold difference in acidity or alkalinity. A low pH indicates a high concentration of hydrogen ions, while a high pH indicates a low concentration of hydrogen ions. Therefore, pH is the correct answer to the given question.

A solute is a substance that dissolves in a solvent. When a solute is added to a solvent, it disperses evenly throughout the solvent, creating a solution. The solute particles become surrounded by the solvent particles, forming a homogeneous mixture. This process is known as dissolution. Examples of solutes include salt, sugar, and various chemicals that can dissolve in water or other solvents.

An atom is the smallest unit of matter that cannot be broken down by chemical means. It consists of a nucleus, which contains protons and neutrons, and electrons that orbit the nucleus. Atoms combine to form molecules and compounds, but they themselves cannot be broken down into smaller particles by chemical reactions. Cells are the basic structural and functional units of living organisms, elements are substances made up of only one type of atom, and compounds are substances made up of two or more different types of atoms.

An element is a pure substance made of only one kind of atom. This means that all the atoms present in an element are identical in terms of their atomic number and chemical properties. Elements are the building blocks of matter and cannot be broken down into simpler substances by ordinary chemical means. Examples of elements include oxygen, carbon, and gold.

A covalent bond forms when atoms share a pair of electrons. In this type of bond, two atoms come together and each contribute one electron to the shared pair. This sharing of electrons allows both atoms to achieve a stable electron configuration, resulting in a strong bond between the atoms. Covalent bonds are commonly found in molecules and compounds composed of nonmetals.

A solvent is a substance in which a solute dissolves and is in greatest concentration in a solution. In other words, it is the component of a solution that is present in larger amounts and has the ability to dissolve other substances. Solvents are commonly used in various processes such as cleaning, manufacturing, and chemical reactions, where they help to dissolve and mix different substances to form a solution.

An ion is formed when an atom, radical, or molecule gains or loses one or more electrons, resulting in a negative or positive charge. This charge is due to the unequal number of protons and electrons in the ion. Therefore, an ion is the correct term to describe a species with a positive or negative charge.

A mixture that is consistent throughout is called a solution. In a solution, the solute is evenly distributed and dissolved in the solvent, resulting in a homogeneous mixture. This means that the components of the solution are uniformly spread out and cannot be easily separated. Solutions can be found in various forms, such as liquid solutions (e.g., saltwater), solid solutions (e.g., alloys), and gaseous solutions (e.g., air).

Cohesion refers to the attraction between substances of the same kind. It is the force that holds molecules of the same substance together. This can be seen in phenomena such as water droplets forming on a surface or the ability of some insects to walk on water. Cohesion plays a crucial role in various natural processes, including the movement of water through plants and the formation of surface tension.

An ionic bond forms through the electrical force between oppositely charged ions. In an ionic bond, one atom transfers electrons to another atom, resulting in the formation of positively charged ions (cations) and negatively charged ions (anions). The attraction between these opposite charges creates a strong bond between the two ions, leading to the formation of an ionic compound. This type of bond is typically found in compounds composed of metals and nonmetals.

A compound is a substance made up of the joined atoms of two or more different elements. It is formed when atoms of different elements chemically combine together in specific ratios. This combination results in the formation of a new substance with different properties from the original elements. Compounds can be found in various forms, such as water (H2O) which is made up of hydrogen and oxygen atoms.

A molecule is the smallest unit of a substance that retains all of its physical and chemical properties. It can be composed of one element or multiple elements bonded together.

Adhesion refers to the attraction between different substances. It is the ability of one substance to stick to another substance. This can occur due to various forces such as van der Waals forces or hydrogen bonding. Adhesion is responsible for phenomena like capillary action, where water can "climb" up a narrow tube against gravity. It is also the reason why water droplets stick to surfaces instead of forming perfect spheres.

Hydrogen bonds occur between molecules that have a hydrogen atom bonded to a highly electronegative atom, such as oxygen or nitrogen. In the case of water molecules, the oxygen atom is highly electronegative and attracts the hydrogen atoms of neighboring water molecules. This attraction creates a weak bond known as a hydrogen bond. Therefore, the positive region of one water molecule is attracted to the negative region of another water molecule through hydrogen bonding.

A substance that removes protons (H+ ions) from a solution is called a base. Bases are characterized by their ability to accept protons, thereby decreasing the concentration of H+ ions in a solution. They are typically bitter in taste, have a slippery texture, and turn red litmus paper blue. Examples of bases include sodium hydroxide (NaOH) and ammonia (NH3).

A substance that releases protons (H+ ions) in solution is known as an acid. Acids are characterized by their ability to increase the concentration of H+ ions when dissolved in water. They typically have a sour taste and can react with bases to form salts and water. Some common examples of acids include hydrochloric acid (HCl), sulfuric acid (H2SO4), and acetic acid (CH3COOH).