Atomic Structure Atomic Models and Isotopes

The positive particles of an atom are 

• electrons 
• positrons 
• neutrons 
• protons 

the central region of an atom where its neutrons and protons are is its 

• nucleus 
• electron cloud
• core 
• center 

Particles in an atom that are neutral and have no charge are 

• negatrons 
• electrons 
• neutrons 
• protons 

What is the mass number?

• the number of protons
• the sum of the number of protons and the number of neutrons in the nucleus of an atom 
• the number of electrons
• the number of neutrons

an atom with atomic number 6 would have how many protons 

• 6
• 12
• 3
• cannot be determined 

An atom has an atomic number of 15 and a mass number of 31. How many protons are there in the atom?

• 15
• 31
• 16
• 47

An atom has 5 protons and 7 neutrons. What is the mass number of the atom?

• 5
• 7
• 2
• 12

An atom has an atomic number of 19 and a mass number of 29. How many neutrons are in the atom?

• 30
• 19
• 10
• 38

Tags

NGSS.MS-PS1-1

How many electron shells/levels does this atom have?

• 1
• 2
• 3
• 4

Look at this picture of Argon off the periodic table. Which of the following is true for this element?

• 18 protons

• 40 protons

• 22 protons

• 21.9 protons

Tags

NGSS.MS-PS1-1