Unit 1 Exam A is for Atoms

In terms of the sequence of the scientific method, what is the immediate purpose of doing an experiment?

• drawing conclusions
• gathering data
• asking the question 
• answering your claim

Who discovered the electron?

• Cassandra Bouakka
• Neil Bohr 
• John Dalton 
• J.J. Thomson

The mass number of an atom is equal to which of the following?

• the number of electrons circling the nucleus of an atom
• the number of protons in a nucleus
• the number of protons plus the number of neutrons in a nucleus
• the number of protons plus the number of electrons in an atom

Nitrogen (N₂) is made up of 99.632% ¹⁴N and 0.368% ¹⁵N. The atomic mass of ¹⁴N is 14.003 amu. The atomic mass of ¹⁵N is 15.000 amu. What is the average atomic mass of nitrogen?

• 14.007 amu
• 15.00 amu
• 155.00 amu
• 1.40 amu

What is the maximum number of electrons that can occupy a box in an orbital filling diagram at any energy level?

• 2
• 8
• 18
• 32

A material weighs 8 grams and takes up 2 cubic centimeters of space. What is the material's density in grams per cubic centimeter (g/cm³)?

• 10 g/cm ³
• 4 g/cm ³
• 2 g/cm ³
• 6 g/cm ³

A balloon is a sphere with a radius of 5.0 m. The force of air against the walls of the balloon is 45 N. What is the air pressure inside the balloon? (surface area = 12.56 x radius ²; 1 Pa = 1 N/m ²)

• 1.4 x 10^–1 Pa
• 3.6 x 10 ² Pa
• 3.6 x 10^–2 Pa
• 1.4 x 10 ³ Pa

The independent variable goes on the x-axis and the dependent variable goes on the y-axis.

• True
• False 

Which of the following is in the same period as Cl?

• Sn
• I
• P
• Hg

The first ionization energy decreases from top to bottom within a group.

• True 
• False