Here are the answers for the questions you provided:
Question 17: Match the molecule or compound to the type of bond found between the elements.
- NaCl: b. ionic bond
- MgBr2: b. ionic bond
- CO2: a. covalent bond
- SO2: a. covalent bond
Question 18: Match the state of matter to its description.
- particles are tightly packed and vibrate in place; definite shape and volume: c. solid
- particles are loosely packed and slide past one another; indefinite shape but definite volume: a. liquid
- particles are far apart and move at fast speeds; indefinite shape and volume: b. gas
Question 19: Match the trend on the periodic table to its description.
- a measure of how strongly atoms attract bonding electrons to themselves: c. electronegativity
- the amount of energy required to remove an electron from an atom or molecule: b. ionization energy
- a measure of the size of an atom: a. atomic radius
Question 20: Using what you know about the trend of electronegativity on the periodic table, which of the following elements would be the most electronegative?
a. Fluorine
Question 21: Match the following words to their descriptions.
- the smallest unit of matter: Atom
- two atoms held together by an ionic bond: Ionic compound
- two atoms held together by a covalent bond: Molecule
- Si: Silicon (an element)
- NaCl: Sodium chloride (an ionic compound)
- CO2: Carbon dioxide (a covalent compound)
(Note: In Question 21, the descriptions associated with "Si", "NaCl", and "CO2" may not have specific matching descriptions in your provided options. If given a specific context, corrections may apply.)