Exam #3 Prep Flashcards
A polar covalent bond is created when…
two atoms share their bonding electrons unequally
What are trihalomethanes?
chemical compounds in which three of the four hydrogen atoms of methane (CH4) are replaced by halogen atoms (halogen atoms: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At))
Which of the following has the highest MCL in drinking water in the US?
nitrates
What is reverse osmosis used for?
to remove dissolved salts from sea water
The correct name for CuO is
copper (II) oxide
What is electronegativity?
a measure of an atom’s attraction for an electron in a chemical bond
What is biological oxygen demand (BOD)?
A measure of the amount of dissolved oxygen microorganisms use up as they decompose organic wastes found in water
The EPA regulates the presence of nitrates and nitrites in water because…
they interact with the blood and limit its ability to transport oxygen
Most polyatomic ions…
have a negative charge
The main reason that water supplies are “chlorinated” is…
to kill disease-causing organisms in the water
The fact that carbon (C) is less electronegative than nitrogen (N) means that in a C Picture N bond, the…
shared electrons are closer to the N atom than to the C atom
If the lead concentration in water is 1 ppm, then we should be able to recover 1 mg of lead from ____ L of water.
1
How many joules are required to heat 2.0 L of water from 20°C to its boiling point of 100°C? The specific heat of water is 4.18 J/g•°C and the density of water is 1 g/mL.
6.7 × 10^5 J
When table sugar (sucrose, C12H22O11) dissolves in water, which type(s) of attraction between water and sugar molecules occur(s)?
hydrogen bond
polar-polar interactions
A student wants to prepare exactly 250 mL of a 0.500 M aqueous potassium hydroxide solution. What mass of potassium hydroxide (molar mass = 56.10 g/mol) must the student dissolve in the 250 mL of solution?
7.01g
