C2 Flashcards
What is an element?
A substance that cannot be broken down into simpler substances by chemical means.
What is a compound?
A substance formed when two or more elements chemically bond together.
What is a mixture?
A combination of two or more substances that are not chemically bonded.
True or False: Elements can be broken down into simpler substances.
False
Give an example of a compound.
Water (H2O)
What distinguishes a mixture from a compound?
In a mixture, the components retain their individual properties and can be separated physically.
Fill in the blank: An example of an element is __________.
Oxygen (O)
What is the chemical formula for common table salt?
NaCl
True or False: Mixtures have a fixed composition.
False
What technique can be used to separate a mixture?
Filtration, distillation, or chromatography.
What is the smallest unit of an element?
An atom.
What is a homogeneous mixture?
A mixture that has a uniform composition throughout.
What is a heterogeneous mixture?
A mixture that has distinct, separate phases or components.
What is the process of separating a liquid from a solid using a filter called?
Filtration.
Fill in the blank: The chemical formula for carbon dioxide is __________.
CO2
What does the term ‘solute’ refer to in a solution?
The substance that is dissolved.
What does the term ‘solvent’ refer to in a solution?
The substance that dissolves the solute.
True or False: All mixtures are homogeneous.
False
What is the law of conservation of mass?
Mass is neither created nor destroyed in a chemical reaction.
What is the difference between an ionic compound and a covalent compound?
Ionic compounds are formed by the transfer of electrons, while covalent compounds are formed by the sharing of electrons.
What is an example of a physical change?
Melting ice.
What is an example of a chemical change?
Burning wood.
What is a pure substance?
A material made of only one type of particle.
Fill in the blank: The atomic number represents the number of __________ in an atom.
Protons
What is the periodic table?
A tabular arrangement of elements based on their atomic number and properties.
What is a molecule?
Two or more atoms bonded together.
True or False: Compounds can be separated by physical means.
False
What is a chemical reaction?
A process that involves the rearrangement of the molecular or ionic structure of a substance.
What is the formula for calculating the number of neutrons in an atom?
Number of neutrons = Atomic mass - Atomic number.
What type of bond occurs when electrons are shared between atoms?
Covalent bond.
What type of bond occurs when electrons are transferred from one atom to another?
Ionic bond.
What is the result of a chemical change?
Formation of new substances.
What is the term for the amount of substance in a given volume?
Concentration.
What is an alloy?
A mixture of two or more metals.
Fill in the blank: The process of heating a liquid to form vapor and then cooling it to form a liquid is called __________.
Distillation.
