CHEM. 114 FINAL
the most common ocidation numbers of Na, Cl and O respectively are _________.
+1,-1,-2
What dosage in grams/kilograms of body weight does a 225 pound man receive if he takes two 250. mg of penicillin? (1ib=453.6 grams)
0.00490 g/kg
a solutin contains a magnesium ion concentration of 12.5 meq/L. calculate the calcium ion concentration in mol/L
0.00625 mol/L
a medical order reads " administer 855 units of heparin SC." the vial contains 15,500 units/cc/ How many millileters should be administered? (1mL=1cc)
0.0552 mL
the density of carbon tetrachloride is 1.59 g/mL. what is the volume, in leters, of 225g?
0.142 L
a sample of water contains 15.5 mg of cyanide in 100. Kg of solution. Calculate the amount of cyanide in ppm.
0.155 ppm
how many moles are there in 1.95 ounces of pure gold? (1ounce=28.4 grams)
0.281 moles
convert 15.9 g/cm^3 to ib/in^3. (1 ib = 453.6 grams, 1 in= 2.54 cm)
0.574 g/cm^3
calculate the pressure (atm) required to compress a sample of gas from 12.5 L at 0.975 atm to 9.75 L
1.25atm
a food calorie (Cal) = calories
1000
what is the molar mass of nitrogen tricholoride?
120.365g/mol
you have 75.0 mg of a radioactive material with a half- life of 36.o hours. how much of the material remains after 3 days?
18.8 mg
a 50.0 mL portion of a stock solution was diluted to 475 mL. if the resulting solution was 2.00M, what was the molarity of the original stock solution?
19.0 M
calculate the number of grams of chlorine gas present in a 7.55 L container at 45.0C if the gas exerts a pressure of 725 mm of mercury
19.6 grams
how many valence electrons are in Mg, Mn, and N respectively?
2,2,5
34.8 grams of solution absorbed 2.55 kilocalories of energy as its temperature increased from 25.2C to 56.7C. calculate the specific heat of the solution in cal/gC
2.33 cal/gC
which sublevel has the lowest energy?
2s
how many rams of water can be produced from 5.50 grams of aluminum hydrozide? use th balanced equation below. ( molar mass of Al(OH)3= 78.0036 g/mol, molar mass of HCl = 36.4606 g/mol, molar mass of AlCl3 = 133.3396 g/mol, molar mass of H2O= 18.0153 g/mol) Al(OH)3(s) + 3HCl (aq) --> AlCl3 (aq) + 3H2O (l)
3.81 grams
A Be+2 ion will have ____ protons and ____ electrons.
4,2
convert 2.0x 10^22 J to Cal. (1cal =4.18J)
4.8x10^18 Cal
How many neutrons are in a neutral atom of Germanium-72?
40
how many grams of calcium carbonate should be used to produce 25.0 grams of calcium oxide? use the balanced equation below. ( molar mass of CaCO3= 100.0869 g/mol, molar mass of CaO= 56.0774 g/mol, molar mass of CO2= 44.0095 g/mol) CaCO3 (s) ---> CaO (s) + CO2 (g)
44.6 grams
how many valence electrons are in a an atom of phosphorus?
5
the d subshell has ___________ orbitals and can hold a maximum of __________ electrons.
5, 10
in a triple bond, ______ electrons are shared between two atoms.
6
avogadro's number says that 1 mole of atoms is equal to ______ atoms.
6.022x10^23
the percent yield of a reaction was 65.3%. if the theoretical yield was 10.9 grams, calculate the actual yield.
7.12 grams
what is the molar mass of calcium hydroxide?
74.093 g/mol
elements are most stable when they have ______ electrons in their outer shell
8
the lewis dot structure for Br- would have ______ dots around its symbol.
8
express the number 0,0008974736 to four sig figs using scientific notation.
8.975 x 10^-4
how many grams are there in 0.725 moles of tin?
86.1 grams
how many grams of glucose (C6H12O6) would be needed to make 2.50x10^2 mL of a 0.200M glucose solution?
9.01 grams
__________ is how close to the actual value a measurement is.
Accuracy
choose the correct net ionic equation for the following reaction. NaBr (aq) + AgNO3---.>
Ag^+ (aq) + Br^- (aq) ---> AgBr(s)
Lithium, potassium and cesium are examples of
Alkali metals
which of the following atoms has the biggest size (radius)?
Ba
________ law can be expressed as PiVi=PfVf
Boyle's
the ability to burn is a ______ property.
Chemical
Which of the following elements is an example of a halogen?
F
A property that can be observed without changing the composition of the matter is a ______ property.
Physical
"there is 125 ml of solution" is an example of a ______ observation of a physical property
Quantitative
_________ law says that when a nonvolatile solute is added to a solvent, the vapor pressure of the solvent decreases in proportion to the concentration of the solute.
Raoult's
what neutral atom has the following electron configuration? [Kr] 5s24d105p4
Te
if an atom loses electrons it becomes a ____ and has a ____ charge.
cation, +
______ law says that the volume of a gas volume varies directly with the absolute temperature if the pressure and number of moles of the gas are constant.
charles'
the general form below represents a _____ reaction. A + B ----> C
combination
________ law is used when a sample of gas undergoes change involving volume, pressure and temperature at the same time.
combined
________ is the amount of solute dissolved in a certain amount of solution.
concentration
a _______ reaction produces two or more products from a single reactant.
decomposition
a reaction with a positive change in H value is a ________ reaction.
endothermic
________ is the measure of the statistical distribution of energy in a system.
entropy
a property of matter that depends on how much matter is present is a ______ property.
extensive
In the argon atom represented as 40Ar, there are 18 protons and 40 neutrons. t or f
false
K+ and KR are isoeletronic. t or f
false
Solute concentration has an impact on physical properties but not chemical properties. t or f
false
Water is an excellent solvent for nonpolar molecules. t or f
false
covalent bonds are most often associated with bonds between two metals. t or f
false
the measure of the attractive forces exerted among molecules at the surface of a liquid is viscosity. t or f
false
the molar mass for oxygen gas is 15.9994 g/mol. t or f
false
the number 0.025465 has 6 significant figures.
false
a reaction at equilibrium __________
has equal rates of forward and reverse reactions, has products being consumed and formed at the same rate.
when water flows into the cell and does not stop _______ can occur.
hemolysis
Mixtures can be either homogeneous or _____________
heterogeneous
a 1.0 M KCl solution is _______ to a 0.50 M NaCl solution.
hypertonic
A 0.25 M KCl solution is _____ to a 0.25 M CaCl2 solution.
hypotonic
________ law can be expressed as PV=nRT
ideal
if a solute is present, the boiling point of the solution _______ and the freezing point ________
increases, decreases
__________ solutions have identical osmotic pressures.
isotonic
a 0.15 M NaCl solution is ______ to a 0.30 M glucose (C6H12O6) solution.
isotonic
the tyndall effect is the ______
light scattering ability of colloids
which of the following is considered a symmetrical shape?
linear, trigonal planar, tetrahedral
reactions tend to occur faster in the ______ state and slowest in the ______ state.
liquid, solid
the density of an object is the ratio of its ______ to ______
mass, volume
a step by step description of how reactants become products is the _______ of a reaction.
mechanism
an ionic bond is between a ______ and a _______
metal, nonmetal
a _________ is an element that typically has more than 4 electrons in its outer shell and will ________ electrons to get to the octet.
nonmetal, gain
any chemical change in solution that results in one or more insoluble products is an _____ reaction.
precipitation
consider the following set of masses taken for a wooden block. if the true value of the mass is 40.0 grams, which of the following is the best statement about the masses measured below? 20.4grams 20.5 grams 20.4 grams
precise, but not accureate
what kind of particle can be found inside the nucleus of an atom.
protons and neutrons
the substances that undergo change in a chemical reaction are the ____
reactants
A ______ solution contains all of the solute that can be dissolved at a certain temperature.
saturated
the general form below represents a _______ reaction. A + BC ---> B + AC
single - replacement
the specific heat of a substance is _______.
the amount of heat required to raise the temperature of one gram of a substance by one degree Celsius.
the maximum amount of product that can be produced in a reaction is the ________.
theoretical yeild.
a ______ is used for measuring the heat energy absorbed or released in a chemical reaction.
thermometer
what is the shape of ammonia (NH3)?
trigonal pyrarmidal
A quantitative observation always involves a measurement of the property in question.
true
Arsenic is an example of a metalloid.
true
Chlorine has a higher electronegativity than sodium.t or f
true
The term for atoms of the same element having different masses due to a different number of neutrons is isotope.
true
in genereal, a liquid will have a higher entropy than a solid state. t or f
true
osmosis is the movement of solvent from a dilute solution to a more concentrated solution through a semipermeable membrane. t or f
true
the correct formula for carbonate is CO3^2- t or f
true
the SI unit for temperature is ______
Kelvin
which of the following elements has the highest ionization energy?
Ne
a catalyst speeds up a reaction by lowering the _______.
activation energy
what is produced when magnesium - 27 undergoes beta emission?
aluminum-27
the branch of chemistry that is applied in measuring the concentration of air pollution is _________
analytical
in a neutral atom, __________ equals the number of electrons.
atomic number