IGCSE CHEM_CHAP 2.1_Elements, compounds and mixtures

Element

A pure substance made from only one type of atom that cannot be broken down further; Nguyên tố.

Compound

A substance made from two or more elements chemically bonded together; Hợp chất.

Mixture

A substance consisting of two or more elements or compounds that are not chemically bonded together; Hỗn hợp.

Pure substance

A substance, such as an element, that consists of only one type of particle and cannot be further simplified; Chất tinh khiết.

Chemical bond

The force that holds atoms together in a compound, formed when elements react with each other; Liên kết hóa học.

Chemical reaction

A process required to break apart the chemical bonds between elements in a compound; Phản ứng hóa học.

Element

What is a substance made from only one type of atom?

Pure substances

What classification is given to elements because they cannot be broken down further?

Compound

What is a substance made from two or more elements that have reacted with each other?

Chemical bonds

What forms between atoms when elements react to create a compound?

Chemical reaction

What is needed to break apart the chemical bonds between elements in a compound?

Mixture

What is a substance made up of two or more elements or compounds not chemically bonded together?

Separation techniques

What can be used to separate the components of a mixture?

Filtration, simple distillation, and crystallisation

What are three examples of separation techniques for mixtures?

They remain unchanged

What happens to the chemical properties of each substance within a mixture?

Air and saltwater

What are two examples of mixtures provided in the notes?

Nitrogen and oxygen

Which molecules primarily make up the mixture known as air?

One

How many types of atoms are found in an element?

Two or more

How many elements must react to form a compound?

Elements or compounds

What two types of substances can be combined to form a mixture?

No

Are the substances in a mixture chemically bonded?

Yes

Are the atoms in a compound chemically bonded?

Element

Which type of substance is copper (Cu)

Compound

Which type of substance is water (H2O)?

Mixture

Which type of substance is air?

Compound

Which type of substance is carbon dioxide (CO2)?

Element

Which type of substance is oxygen (O2)?

They cannot be broken down further

Why are elements considered "pure"?

Chemically reacted

What must have happened to elements for them to be part of a compound?

Through chemical reactions

How can elements in a compound be separated?

Physical separation (separation techniques)

How can components in a mixture be separated?

Saltwater

Which specific mixture mentioned consists of a solid dissolved in a liquid?

Atoms

Elements are made from only one type of what?

Chemical bonds

What is "broken" when a chemical reaction separates a compound?