Chemistry S1

First Semester Chemistry FlashCards

Chemistry

The scientific study of matter, its properties, its composition, and the changes it undergoes during reactions.

What are the three common states of matter?

Solid, liquid, gas

What is an element?

A substance made of only one type of atom.

What is a compound?

A substance made of two or more different elements chemically bonded together.

What is Matter

Anything that has mass and takes up space.

What is a mixture?

Two or more substances physically combined but not chemically bonded.

What is an atom?

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

What are the three main subatomic particles?

Protons, neutrons, and electrons.

What charge does a proton have?

Positive (+1).

What charge does a neutron have?

Neutral (0).

What charge does an electron have?

Negative (−1).

Where are protons found?

In the nucleus.

Where are neutrons found?

In the nucleus.

Where are electrons found?

In the electron cloud/energy levels around the nucleus.

What is the nucleus of an atom?

The small, dense centre of an atom that contains protons and neutrons.

What is the atomic number?

The number of protons in an atom.

What does the atomic number tell you?

Which element the atom is.

What is the mass number?

The number of protons + neutrons.

How do you calculate the number of neutrons?

Mass number − atomic number.

In a neutral atom, how do protons and electrons compare?

They have equal numbers.

What is the periodic table?

A table that organizes the chemical elements.

What are the horizontal rows of the periodic table called?

Periods.

What are the vertical columns called?

Groups (or families).

How many periods are in the periodic table?

7.

How many groups are in the periodic table?

18.

Why do elements in the same group often have similar properties?

They have similar arrangements of their outer electrons.

What is a chemical symbol?

A one- or two-letter abbreviation representing an element.

What does the subscript in H₂O mean?

There are 2 hydrogen atoms.

How many oxygen atoms are in H₂O?

1.

How many carbon atoms are in CO₂?

1.

How many oxygen atoms are in CO₂?

2.

What is a physical change?

A change where no new substance is formed.

Give an example of a physical change.

Ice melting.

What is a chemical change?

A change that produces one or more new substances.

Give an example of a chemical change.

Iron rusting.

What are metals generally good at conducting?

Heat and electricity.

What are nonmetals generally like?

They are usually poor conductors of heat and electricity.

What are metalloids?

Elements with properties between those of metals and nonmetals.