Chemical Substances and Reactions Quiz

The number of protons in an atom's nucleus. It defines the element.

Atoms of the same element with different numbers of neutrons. This means they have different masses.

The average mass of all isotopes of an element found in nature.

The outermost shell or energy level of an atom.

The number of protons and neutrons in an atom's nucleus. It indicates the atom's mass.

An atom that has gained or lost electrons, giving it a net positive or negative charge.

Elements that easily donate electrons to achieve a full outer shell. They are highly reactive.

Elements that easily accept electrons to achieve a full outer shell. They are also highly reactive.

A group of elements that have similar chemical properties due to having the same number of valence electrons.

Elements in Group 1 of the periodic table. They readily lose one electron, forming 1+ ions.

Elements in Group 7 of the periodic table. They readily gain one electron, forming 1- ions.

Elements in Group 0 (or 8) of the periodic table. They have a full outermost shell and are extremely unreactive.

A type of bonding that occurs between metal atoms. Electrons are delocalized, allowing for conductivity.

A type of bonding that occurs between a metal and a non-metal. Electrons are transferred, forming oppositely charged ions.

They can donate a variable number of electrons, resulting in multiple possible ion charges (e.g., Fe2+ and Fe3+).

A bond formed by the sharing of electrons between two atoms.

Groups of atoms that have a net electrical charge.

A substance formed by the attraction between positively charged metal ions and negatively charged nonmetal ions.

A type of ionic compound that consists of a metal cation and a nonmetal anion.

A group of atoms held together by covalent bonds.

A bond where two atoms share one pair of electrons.

A bond where two atoms share two pairs of electrons.

A bond where two atoms share three pairs of electrons.

A giant structure where many atoms are bonded together by covalent bonds.

A substance with the same type of atoms but arranged differently (e.g., diamond and graphite).

A substance that can conduct electricity, usually in liquid form (molten) or dissolved in water.

The number of particles (atoms or molecules) in one mole of a substance.

A substance made up of two or more different types of atoms chemically bonded together.

A representation of a chemical reaction using symbols.

Any combination of elements and/or compounds that are not chemically bonded together.

A mixture where one substance is dissolved into another, usually a liquid.

The process of separating insoluble solid particles from a liquid.

The process of separating a dissolved solid from a solution by evaporating the solvent.

The process of separating a mixture of liquids by heating and condensing the vapors, based on their different boiling points.

A specific mixture designed for a particular purpose with carefully measured amounts of substances.

A technique used to separate components of a mixture, often based on their different attractions to a stationary phase.

The ratio of the distance a substance travels in chromatography compared to the distance the solvent travels.

The state of matter with a fixed volume but not a fixed shape. Particles are free to move past each other.

Adding energy, usually heat, to overcome forces of attraction between particles and change a solid to a liquid or a liquid to a gas.

A model of the atom that proposed a sphere of positive charge with electrons embedded within.

The mass of a substance containing 6.022 x 10^23 particles (atoms or molecules).

The number of moles of a substance is equal to its mass in grams divided by its relative atomic or formula mass.

The ratio of moles of one substance to another in a chemical reaction.

The reactant that is completely consumed first in a chemical reaction, limiting the amount of product that can be formed.

A solution's concentration expressed as the number of moles of solute per liter of solution.

A measure of a substance's ability to donate electrons in a chemical reaction. Metals higher on the reactivity series are more reactive.

When a more reactive metal displaces a less reactive metal from a compound, like Zinc displacing Copper from Copper Sulfate.

A solid substance formed when two solutions are mixed together.

The process of extracting metals from their ores by heating them with carbon. It's used for metals less reactive than carbon.

A chemical reaction where the products can turn back into the original reactants.

A chemical reaction that involves the gain of electrons. The opposite of oxidation.

The amount of product formed compared to the maximum theoretical amount possible.

A chemical reaction that involves the loss of electrons. The opposite of reduction.

The speed at which a reaction happens.

A substance that releases H+ ions when dissolved in water, having a pH less than 7.

A substance that speeds up a reaction but isn't used up in the process.

The minimum energy needed for a reaction to occur.

A substance that releases OH- ions when dissolved in water, having a pH greater than 7.

A neutralization reaction is where an acid and alkali react to produce salt and water. The resultant solution has a pH of 7.

A substance that changes color depending on the acidity or alkalinity of a solution.

A chemical compound formed when the hydrogen of an acid is replaced by a metal.

A logarithmic scale that measures the concentration of H+ ions in a solution. A pH of 3 has 10 times the concentration of H+ ions compared to a pH of 4.

A substance that turns pink in acidic solutions.

The point in a titration where the acid and base have completely reacted.

A measure of the amount of a substance in a given volume of solution.

A chemical reaction that involves the release of heat energy.

A chemical reaction that absorbs heat energy from the surroundings.

The amount of product formed in a chemical reaction.

A state where the rates of the forward and reverse reactions are equal, resulting in no overall change in the amounts of reactants and products.

A principle stating that a system at equilibrium will shift to counteract any changes in conditions.

Increasing the pressure on a system at equilibrium will favor the reaction that produces fewer moles of gas.

Increasing the concentration of a reactant will shift the equilibrium to the right, favoring the forward reaction.

Increasing the temperature will favor the endothermic reaction, while decreasing the temperature will favor the exothermic reaction.

A process used to produce ammonia (NH3) from nitrogen (N2) and hydrogen (H2) gases.

An alloy of copper and tin.

An alloy of copper and zinc.

An alloy of iron and carbon, often containing chromium or nickel to resist corrosion.

The slow destruction of a material due to chemical reactions.

A protective coating of a more reactive metal applied to another metal to prevent corrosion.

The process of coating a metal with zinc to prevent corrosion.

Gases that trap heat in the Earth's atmosphere, causing a warming effect.

The gradual increase in Earth's average temperature due to the enhanced greenhouse effect.

A chemical reaction where larger molecules are broken down into smaller molecules, often by heat and a catalyst.

A saturated hydrocarbon with only single bonds between carbon atoms. The general formula is CnH2n+2.

An unsaturated hydrocarbon with at least one double bond between carbon atoms. The general formula is CnH2n.

The process of joining monomers together to form a long chain polymer, often triggered by heat or a catalyst.

A type of polymerization where monomers with a double bond are joined together, breaking the double bond and forming single bonds.

A type of polymerization where two monomers with functional groups react to form a polymer, releasing a small molecule (often water) in the process.

A type of organic compound containing an -OH functional group attached to a carbon atom. Their names always end in 'ol'.

A type of organic compound containing a -COOH functional group attached to a carbon atom. Their names always end in 'oic acid'.

A type of polymer formed by the condensation polymerization of bifunctional monomers, containing ester linkages within its chain structure.

The strength of an acid refers to its ability to donate hydrogen ions (H+). A strong acid fully dissociates in solution, meaning all its molecules release H+ ions. A weak acid only partially dissociates, with only a small fraction of molecules releasing H+ ions.

The concentration of an acid is the amount of acid dissolved in a given volume of solution. A higher concentration means more acid molecules per unit volume, resulting in a higher concentration of H+ ions.

Ionic compounds, when melted, can conduct electricity because their ions are free to move. The positive ions (cations) move towards the negatively charged electrode (cathode), while the negative ions (anions) move towards the positively charged electrode (anode).

In electrolysis, the process of gaining electrons is called reduction, and it always occurs at the cathode. Cations, being positively charged, attract electrons and are reduced.

In electrolysis, the process of losing electrons is called oxidation, and it always occurs at the anode. Anions, being negatively charged, lose electrons and are oxidized.

Electrolysis can be used to extract metals from their compounds or purify them. In the case of aluminum oxide, the oxygen produced at the anode reacts with the carbon anode, requiring its replacement.

Cryolite is added to molten aluminum oxide to lower its melting point, making the extraction process more efficient and cost-effective.

In electrolysis of ionic solutions, the less reactive ion will be attracted to the electrodes and undergo reduction or oxidation. For example, in the case of sodium chloride solution, H+ ions are less reactive than Na+ ions and will be reduced at the cathode, producing hydrogen gas.

An energy profile diagram visually represents the energy changes that occur during a chemical reaction. The Y-axis represents potential energy, while the X-axis represents the progress of the reaction.

The breaking of a chemical bond requires energy, while the formation of a new chemical bond releases energy. The net energy change during a reaction is determined by the difference between the energy required for bond breaking and the energy released by bond formation.

Each type of covalent bond requires a specific amount of energy to break it. For example, a carbon-hydrogen bond requires 413 kJ/mol to break.

A colorless, odorless, and toxic gas. It binds to red blood cells preventing oxygen transport, leading to fatal consequences.

A type of atmospheric pollution caused by the burning of fossil fuels. It dissolves in water forming acid rain.

Water that has low levels of salt and microbes, making it safe to drink. It's a crucial resource around the world.

The process of removing salt from seawater to make it drinkable. Requires significant energy input.

When water moves from a high concentration area to a low concentration area through a semi-permeable membrane. This can occur in living organisms.

Molecules that contain carbon as the backbone of their structure. They are found in many natural and man-made materials, including crude oil.

A mixture of hydrocarbons found underground, mainly made up of alkanes. It is a valuable source of energy and raw materials.

A process that separates hydrocarbons in crude oil based on their boiling points. It's crucial for producing useful fuels like gasoline.

The attraction between molecules. Stronger intermolecular forces lead to higher boiling points and greater viscosity.

A fraction of hydrocarbons used as fuel in cars. It's a flammable mixture of short-chain alkanes.

A functional group that breaks the double bond in alkenes. It is commonly used in chemical reactions.