Atoms, elements and compounds

Front

What are the vertical columns of the periodic table called?

Back

Groups

Front

What does an atom consist mostly of?

Back

Empty space with electrons orbiting a dense nucleus made of protons and neutrons.

Front

What do the elements B, Al, Ga, In, Tl have in common?

Back

They have similar physical and chemical properties.

Front

Why was Dalton's original atomic theory changed?

Back

There was new evidence to support the modifications.

Front

How are elements arranged in the periodic table?

Back

By increasing atomic number.

Front

What is an atom?

Back

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

Front

What is a compound?

Back

A substance formed when two or more elements chemically bond together.

Front

What is the difference between an element and a compound?

Back

An element is a pure substance made of only one type of atom, while a compound is made of two or more different types of atoms bonded together.

Front

What is the atomic number?

Back

The number of protons in the nucleus of an atom, which determines the element's identity.

Front

What is a molecule?

Back

A group of two or more atoms bonded together, which can be of the same or different elements.