AP Chemistry Unit 1 and 2

At 80'C, KBr's solubility is:

• 100

• 90

• 80

• 0

Tags

NGSS.HS-PS1-5

NGSS.HS-PS3-4

What is the oxidation number of S₈?

• 0

• 8

• 6

• 16

In NCl₃, Chlorine has an oxidation number of

• 1-

• 1+

• 3-

• 3+

Which liquid has the highest vapor pressure at 75^oC?

• ethanoic acid

• ethanol

• propanone

• water

How many moles of H₂ is needed to react with 2 moles of N₂?

• 6

• 3

• 2

• 1

Tags

NGSS.HS-PS1-7

How many neutrons does the isotope below have?     ⁸⁹ ₃₆Kr

• 53

• 36

• 89

• 125

Fluorine has an atomic number of 9. What can you conclude about an atom of fluorine from this fact?

• it has 9 protons

• it weighs 9 grams

• it has 9 electron shells

• it has a boiling point of 9 degree celsius

Tags

NGSS.HS-PS1-1

What is meant by the term "sea of electrons"?

• It's what we call all the free floating electrons in a metal.

• It's what we call electrons that are floating in a liquid.

• It's the total number of electrons in a metal atom.

• It's the total number of electrons in the ocean.

Tags

NGSS.HS-PS2-5

London forces are stronger in heavier atoms or molecules, and weaker in lighter atoms or molecules.  Which of these has the strongest London forces?

• F₂

• Br₂

• I₂

• Cl₂

Why does a gas with a lower vapor pressure have a higher boiling point?

• the molecules need more energy to break free of their attractions to other molecules and change phase from liquid to gas

• the forces of attraction between the molecules are strong

• the substance has low volatility

• all of the answers are correct