Chemistry Review Chapter 5

- A molecule is the particle formed when 2 or more atoms are held together by means of covalent bonds

- A compound, the atoms of which are held together by means of bonds that involve electron sharing, is called a covalent compound.

- A binary compound is one that contains 2 and only 2 elements.

- An electrolyte is a substance that conducts electric current when dissolved in water or when melted.

- A compound that consists of ions is called an ionic compound.

- If left outside on a table long enough, a deliquescent substance, such as calcium chloride, will take on enough water to form a liquid solution.

- The bond formed when one atom transfers one or more electrons to a second atom is called an ionic bond.

- An ion is an atom or group of atoms that carries an electric charge because it ahs gained or lost electrons.

- When copper sulfate pentahydrate is heated, water is driven off, leaving behind anhydrous copper sulfate.

- The sulfate ion is an example of a polyatomic ion because it contains 2 different elements.

- The bond formed when 2 atoms share one o more pairs of electrons with each other is called a covalent bond.

- In general, compounds that do not contain carbon are classified as inorganic.

- A chemist can often use the process of distillation to separate 2 liquids from each other.

- A formula shows in a shorthand way the numbers and kinds of elements present in a compound.

- Methane and propane are examples of hydrocarbon because they contain only carbon and hydrogen.

- A molecular substance is one in which atoms are held together by covalent rather that ionic bonds.

- A crystal is a regular, repeating arrangement of atoms, ions, or molecules of a solid.

- CaSO4 x 2H2O is a hydrate because it always contains a fixed ratio of water molecules, to calcium and sulfate ions.

- The forces between the particles of a substance are called interparticle forces.

- Sodium carbonate is a hygroscopic substance because it takes on water molecules, to which it becomes chemically bonded.

- A compound such as methane that contains carbon is generally classified as an organic compound.

- According to the principle called the octet rule, an atom is stable when it has 8 electrons in its outer energy level.

- A chemical combination of 2 or more elements joined together in a fixed proportion - compound

- The capacity to do work - energy

- An observation that makes use of measurement - quantitative

- Can be observed only when there is a change in composition of a substance - chemical property

- The behavior of matter and its characteristics - properties

- Solutions in which water is the solvent - aqueous solution

- The fact that matter can be neither created nor destroyed in a chemical change - law of conservation of mass

- The material that is dissolved in a solution - solute

- Anything that takes up space and has mass - matter

- The combination of chemical symbols that describes the composition of a chemical compound - formula

- Any chemical reaction that gives off energy - exothermic

- The type of change in which the identity of substances does not change - physical change

- The measure of the amount of matter that an object contains - mass

- A solid solution usually consisting of 2 or more metals - alloy

- sulfur (6+) and oxygen - SO3; sulfur trioxide

- aluminum and fluorine - AlF3; aluminum fluoride

- calcium and sulfate - CaSO4; calcium sulfate

- aluminum and carbonate - Al2(CO3)3; aluminum carbonate

- magnesium and phosphorus - Mg3P2; magnesium phosphide

- sodium and oxygen - NA2O; sodium oxide

- copper (+2) acetate - Cu(C2H3O2)2; copper (II) acetate

- ammonium and nitrate - NH4NO3 - ammonium nitrade

- iron (+3) sulfate - Fe2(SO4)3 - iron (III) sulfate

- The strong crystal structure of an ionic compound is one reason ionic compounds have high

- When an atom loses an electron, it becomes a positive ion.

- Atomic mass units are based on the mass of an atom of carbon-12.

- Electron sharing produces molecules.

- J.J. Thompson used a cathode ray to discover the electron.

- In order to separate 2 liquids from each other by distillation, they must evaporate at different temperature.

- All of the following elements are metals excepts chlorine.

- Think of the term octet, octopus, and octagon. Infer the meaning of the prefix oct-. Eight

- Diamond is an allotrope of carbon

- Sugar, which is a substance, can be broken down into carbons, oxygen, and hydrogen. Sugar is a compound.

- Reactions between atoms involve only valance electrons.

- Matter that is large enough to be seen is macroscopic.

- A tug-of-war in which neither side is able to move the other side could be used to model an covalent bond.

- In a Lewis dot diagram, the dots represent the valance electrons in the atom.

- The mass number of an element whose atoms have 12 protons and 13 neutrons is 25.

- Dobereiner’s classification system was based on groups of elements he called triads.

- The scientific statement that says that compounds always have exactly the same composition by mass is the law of definite proportions.

- Noble gases are sometimes used to protect valuable documents because they are unreactive.

- Which of the following pairs of compounds are allotropes? O2 and O3

- Based on its position in the periodic table, the most likely charge of an iodine ion is -1.

- A substance will conduct an electric current if it forms ions in solution.

- Which of the following is not a characteristic of a metal? Brittle

- Coal burns in a furnace, producing light and heat. This reaction is exothermic.

- A physical property of zinc metal is its color.

- Columns of the periodic table are known as groups.

- The second row of the periodic table includes 8 elements.

- When ice melts and becomes liquid water, it has undergone a physical change.

- The properties of a compound are different from the properties of the elements that form it.

- Which of the following is the correct chemical formula for a formula unit of aluminum bromide? AlBr6

- The correct name for Fe2S3 is iron (III) sulfide.