Chapter 2. Worksheet #2-1(Molecules and bonds) #2-2(Properties of solutions) Flashcards
What is a molecule?
A group of two or more chemically bonded atoms
What is the octet rule used to determine?
How atoms will combine to form molecules. Each atom has a tendency to acquire the valence shell of the noble gas in their period
When does an element reach “elemental happiness”?
When its last shells is filled with the maximum number of valence electrons it will be stable. Noble gases are stable and are nonreactive since their shells are filled.
What is an ion?
An ion is an atom that has become electrically charged by gaining/losing electrons
The formation of an ion doesn’t change ____ or ____.
The number of protons or neutrons in an atom
When atoms gain electrons, what do they become?
A negatively charged ion (since they contain more electrons than protons)
When atoms lose electrons, what do they become?
A positively charged ion (since they contain more protons than electrons)
- What is an aqueous solution?
A solution where the solvent is dissolved in water
- What is concentration?
Amount of solute in a given amount of solution
- What is dilution’s effect on concentration?
Decreases it (adds more solvent)
- What is dissolution’s effect on concentration?
Increases it (adds more solute)
- What is evaporation’s effect on concentration?
Increases it (decreases the solvent)
- What is the formula for concentration?
C=m.of solute (g)/v.of solution (L)
- What is the formula for ppm?
ppm=m.of solute (mg)/v.of solution (L)
- What is the formula for mass/volume%?
(%m/v)=m.of solute (g)/v.of solution (ml) x100
