Week 3 HW due 9/1

Front

HORIZONTAL ROWS ON THE PERIODIC TABLE ARE CALLED?

Back

Periods

Front

How many neutrons does Phosphorus have?

Back

16

Front

VERTICAL COLUMNS on the periodic table are called?

Back

Groups

Front

What is the atomic number of an element?

Back

The number of protons in the nucleus

Front

What element has 6 valence electrons and 2 energy levels?

Back

Oxygen

Front

What is the definition of an element?

Back

A pure substance that cannot be broken down into simpler substances.

Front

What is the significance of valence electrons?

Back

They determine an element's chemical properties and its ability to bond with other elements.

Front

What is the difference between protons and neutrons?

Back

Protons are positively charged particles in the nucleus, while neutrons are neutral particles.

Front

What does the atomic mass of an element represent?

Back

The average mass of an element's isotopes, measured in atomic mass units (amu).

Front

What is a chemical symbol?

Back

A one or two-letter notation used to represent an element.