Which of these is a required safety rule for the flame test lab?

• tie long hair back

• wear goggles

• do not reach across the lab bench

• all of these are required

Why do we wet the cotton swap before dipping it into the salt?

• to clean the cotton swab

• to make the salt stick to it

• to prevent the cotton swab from burning

• all of these are true

Which of these could lead to cross contamination?

• dipping an already used cotton swab in the container of salt a second time

• keeping the Bunsen burner clean and free from melted salt

• using only clean distilled water to wet the cotton swabs

• putting used cotton swabs in a separate beaker of tap water

Which of these practices is a good way to store already burned cotton swabs before throwing them in the trash?

• dipping an already used cotton swab in the container of salt a second time

• keeping the Bunsen burner clean and free from melted salt

• using only clean distilled water to wet the cotton swabs

• putting used cotton swabs in a separate beaker of tap water

Which of these practices is a good way to prevent cross contamination?

• dipping an already used cotton swab in the container of salt a second time

• putting used cotton swabs in a separate beaker of tap water

• using only clean distilled water to wet the cotton swabs

• all of these are good ways to prevent cross contamination

Tags

NGSS.HS-LS1-3

Consider the following data:

Cu - blue, green, teal

Na - yellow-orange

K - yellow, orange, pink/lavender

Li - red, light red

Sr - deep red

If the unknown color was yellow-orange, which element is most likely the unknown?

• Cu

• Na

• K

• Li

Consider the following data:

Cu - blue, green, teal

Na - yellow-orange

K - yellow, orange, pink/lavender

Li - red, light red

Sr - deep red

If the unknown color was yellow,orange with some pink, which element is most likely the unknown?

• Cu

• Na

• K

• Li

An atomic emission spectrum is...

• unique to the element

• a complete rainbow

• both of these are correct

• neither of these are correct

Light of a specific frequency is emitted when...

• an electron absorbs energy

• an electron moves down an energy level

• when an electron gets excited

• all of these are true

Tags

NGSS.HS-PS4-3

Atoms only emit light of certain frequencies because...

• electrons move continuously

• electrons move up energy levels

• electrons can only have certain energies

• all of these are true

Tags

NGSS.HS-PS4-3