Atoms, Elements, Molecules and Compounds

What is a compound?

• A substance formed when two or more different elements chemically bond together in a fixed ratio.

• A mixture of two or more substances that can be separated by physical means.

• A single element that cannot be broken down into simpler substances.

• A solution where one substance is dissolved in another.

What is an atom?

• A large particle that makes up molecules.

• The smallest unit of matter that retains the properties of an element.

• A type of chemical bond between two elements.

• A collection of cells that form living organisms.

What is a mixture?

• A combination of two or more substances that retain their individual properties and can be separated by physical means.

• A single substance that cannot be separated into its components.

• A chemical reaction between two or more substances.

• A solution that has uniform composition throughout.

What is an ionic bond?

• A type of bond formed by sharing electrons between atoms.

• A type of bond formed through the transfer of electrons from one atom to another, resulting in the attraction between oppositely charged ions.

• A bond that occurs only in metals and does not involve any charge.

• A weak bond that forms between molecules due to temporary dipoles.

What is the chemical symbol for oxygen?

• O

• Ox

• O2

• O3

What is the chemical formula for water?

• H2O

• CO2

• NaCl

• C6H12O6

What is a chemical reaction?

• A process that leads to the transformation of one set of chemical substances to another, involving the breaking and forming of bonds.

• A method of separating mixtures into their individual components.

• A technique used to measure the temperature of a substance.

• A way to combine different elements without any change in their properties.

What is the difference between a homogeneous mixture and a compound?

• A homogeneous mixture is a chemical combination of elements that cannot be separated by physical means, while a compound contains two or more substances that are evenly distributed.

• A homogeneous mixture contains two or more substances that are evenly distributed and can be separated by physical means, while a compound is a chemical combination of elements that cannot be separated by physical means.

• A homogeneous mixture is always a solid, while a compound can be a solid, liquid, or gas.

• A homogeneous mixture can only be formed from gases, while a compound can be formed from any state of matter.

What is the law of conservation of mass?

• The law of conservation of mass states that mass is created in a chemical reaction.

• The law of conservation of mass states that mass is destroyed in a chemical reaction.

• The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction; it is conserved.

• The law of conservation of mass states that mass can change forms but is not conserved.

What distinguishes a molecule from a compound?

• A molecule consists of only one type of atom, while a compound consists of two or more different elements.

• A molecule can consist of the same or different types of atoms, while a compound specifically consists of two or more different elements.

• A molecule is always larger than a compound.

• A molecule is a type of compound that contains only carbon atoms.