Atoms and Periodic Table

The outermost electrons in an atom are called...

• Cloud electrons

• Orbital electrons

• Far electrons

• Valence Electrons

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Two isotopes of carbon are carbon-12 and carbon -14. This isotopes differ from one another by____

• The number of protons

• the number of electrons

• Atomic number

• the number of neutrons

Which statement is true about all nonmetals EXCEPT for hydrogen?

• They are all liquids at room temperature

• They are all found to the right of the zig-zag line on the periodic table

• They all have 7 valence electrons

• They are all in the noble gas family.

An element with 17 protons, 18 neutrons and 17 electrons is ____

• Chlorine

• Nitrogen

• Bromine

• Argon

Tags

NGSS.MS-PS1-1

An element is in period 3 and in family 1. How many energy levels would the Bohr model of this element have?

• 4

• 3

• 11

• 1

How many neutrons does an element with atomic number 18 and atomic mass 39.948 have?

• 18

• 39

• 22

• 21

Tags

NGSS.MS-PS1-1

Where is most of the mass of an atom located?

• In the electron

• Electron cloud

• In the nucleus

• Evenly spread throughout the atom

How many valence electrons does Magnesium (Mg) have?

• 2

• 4

• 5

• 6

Which element is a metal?

• Calcium

• Fluorine

• Hydrogen

• Iodine

Which element is an alkaline earth metal and in period 4?

• K (19)

• Na (11)

• Br (35)

• Si (14)

• Ca (20)