2nd period Test

States of matter

100

state of matter has a definite shape and volume?

Solid 

200

state of matter where particles are closest together

Solid 

300

example of plasma

Ligthning, starts, plasma TV, Neon lights 

400

state of matter that takes both the shape and volume of its container

Gas

Phase change

100

When water freezes, it changes from:

liquid-solid

200

The change from liquid to gas is called:

Exaporation

300

During melting, the temperature of the substance:

increases

400

• Which phase change occurs when snow directly turns into water vapor on a sunny day without melting?

Sublimation

atoms

100

The element represented by “Fe” is:

Iron

200

How many hydrogen atoms are in C₂H₆?

6

300

In Fe₂(CO₃)₃ how many carbon atoms are there?

3

400

• main difference between a chemical symbol and a chemical formula?

A chemical symbol represents one element, while a chemical formula shows a compound made of several elements.

atomic model

100

The center of an atom is called the

Nucleus

200

Which subatomic particle has a negative charge?

Electron

300

The first person to propose that matter is made of tiny particles called atoms was:

Dalton

400

The number of protons in an atom is called the

Atomic number

Bohrs model

100

Vertical columns in the periodic table are called:

Groups

200

Horizontal rows in the periodic table are called:

Periods

300

Bohrs model for an atom with an atomic number of 20 

Calcium

400

Bohr’s model introduced:

Energy levels