Biol211Ch2

Titanium has an atomic number of 22. How many protons, neutrons, and electrons are in an isotope of titanium with a mass number of 48?

• p=22; n=26, e=22
• p=11; n=26, e=11
• p=22; n=22, e=48
• p=11; n=22, e=48

What numbers must be placed as coefficients in the blanks for the chemical reaction below in order to ensure that matter is conserved?

Fe₃O₄ + __C -> __Fe + __ CO

• 1; 1; 1

• 4; 3; 4

• 2; 1; 2

• 3; 4; 3

Tags

NGSS.HS-PS1-7

Think of squirrels entering and leaving a room as an analogy for a chemical reaction. When is the room at equilibrium?

• When all of the squirrels in the room leave
• When as many squirrels enter as there is space in the room
• When the door is shut
• When equal numbers of squirrels are entering and leaving the room

Tags

NGSS.HS-PS1-6

Which of the following is a trace element in the human body?

• C
• O
• P
• N

Which of the following described atoms would be most likely to form an ionic bond?

• Atom with 4 of 8 valence electrons and 4 atoms with 1 of 2 valence electrons
• Atom with 7 of 8 valence electrons and an atom with 1 of 2 valence electrons
• Atom with 5 of 8 valence electrons and an atom with 3 of 8 valence electrons
• Atom with 2 of 8 valence electrons and an atom with 6 of 8 valence electrons

Tags

NGSS.HS-PS1-2

The covalent bond between two oxygen atoms is best described as:

• Nonpolar
• Polar

Tags

NGSS.HS-PS1-1

Changing the ___ would change an atom into an atom of a different element.

• number of electrons surrounding the nucleus of an atom
• electrical charge of an atom
• number of protons in the nucleus of an atom
• number of neutrons in the nucleus of an atom

Tags

NGSS.HS-PS1-8

Changing the ___ would change an atom into a different isotope of the same element.

• number of electrons surrounding the nucleus of an atom
• electrical charge of an atom
• number of protons in the nucleus of an atom
• number of neutrons in the nucleus of an atom

Tags

NGSS.HS-PS1-8

If a neutrally-charged atom of fluorine has 9 electrons, how many protons does it have?

• There is not enough information to answer
• 8
• 9
• 10

Potassium's atomic number is 19 and its atomic mass is 39. How many neutrons does an atom of potassium have?

• 20

• 19

• 10

• There is not enough information to answer