chemistry final
what is the mass in grams of 2.76 x 10^17 atoms of calcium?
1.84 x 10^-5g
any d orbital can hold up to _______ electrons.
10
the mass/mass percent concentration refers to the number of grams of solute in
100 g of solution
how many protons are in an isotope of sodium with a mass number of 25?
11
consider an isotope of sodium with a mass number of 25. the number of neutrons in this isotope of sodium is
14
the correct symbol for the isotope of carbon with an atomic mass of 14 is
14 C 6
what is the molar mass of Fe2O3?
159.7
what is the molar mass, to three significant figures, of sodium phosphate, Na3PO4?
164 g
according to the octet rule, sulfide ions should have a charge of
2-
what is the molarity of a solution containing 5.00 moles of KCl in 2.00 L of solution?
2.50 M
a can beverage contains 2.8L of liquid. how many nanoliters is this?
2.8 x 10^9 nL
25.0 mL of alcohol is dissolved in water and the solution is diluted to a total final volume of 125 mL. what is the final concentration of ethanol?
20.0 % (m/m)
1.00 mol of neon has a mass of
20.2 g
what is the number of electrons in the nucleus of the Fe2+?
24
what is the mass in grams of 1 mole of N2?
28.02
the average speed of helium gas at room temperature is 1255 m/s. convert this speed to miles per hour (mph).
2807 mph
what is the coefficient of H2O when the following equation is properly balanced with the smallest set of whole numbers? Na + H2O -> NaOH + H2
3
what is 356 expressed in scientific notation?
3.56 x 10^2
calculate the percent composition by mass of S in sulfuric acid, H2SO4.
33%
an atom of the isotope bromine-80 consists of how many protons, neutrons, and electrons?
35p, 45n, 35e
on a hot day, the thermometer reads 95°f. what is the temperature in degrees celsius?
35°c
the measurement 0.000043 m, expressed correctly using scientific notation, is
4.3 x 10^-5 m
how many electrons are present in a silver atom?
47
how many neutrons are in the nucleus of rubidium-85 atom?
48
how many protons are there in the nucleus of cadmium-112?
48
a gas at 5.00 atm pressure was stored in a tank during the winter at 5.0°c. during the summer, the temperature in the storage area reached 40.0°c. what was the pressure in the gas tank then?
5.63 atm
any p orbital can hold up to ________ electrons.
6
what is the molecular mass of a (NH2)2CO?
60.02 g/mol
how many neutrons are in the nucleus of a tin-118?
68
the mass of 1.63 x 10^21 silicon atoms is
7.60 x 10^-2 g
how many grams of glucose are needed to prepare 400. g of a 2.00% (m/) glucose solution?
8.00 g
a 10.0 liter balloon was taken from a temperature of 25.0°c and placed in a freezer at a temperature of -15.0°c. what was the new volume if pressure is constant?
8.66 liters
what is the atomic weight of krypton?
83.80
365 K equals
83°c
the number 9.0652 rounded to three significant figures is
9.07
9.31 g is the same mass as
9310 mg
of the five elements Na, Al, S, Cl, F, the most electronegative is
F
what element has the electron configuration 1s2 2s2 2p6 3s2 3p6 4s2 3d6?
Fe
when 100. g Mg3N2 reacts with 75.0 g H2O, what is the limiting reactant?
H2O
the formula for sulfur dichloride is
SCl2
the atomic mass is defined as
a mass of 1 mole of units of a substance
the energy of an infrared photon is higher than that of
a microwave photon
which of the following measurements has three significant figures? a) 0.510 m b) 510 m c) 0.005 m d) 0.051 m e) 5100 m
a) 0.510 m
which of the following substances contains a nonpolar bond? a) N2 b) NaCl c) NH3 d) MgF2 e) H2O
a) N2
what is 1.78 x 10^-2 expressed as a decimal?
0.0178
calculate the number of moles of xenon in 12.0g of xenon.
0.0914 mol
what is the mass of 0.00100 mol of caffeine, C8H10N4O2?
0.194 g
how many moles are in 67g of gold?
0.34 mol
convert 556mL to quarts. (1L= 1.06qt)
0.589qt
in this reaction, what is the coefficient for calcium oxide? CaO + CO2 -> CaCO3
1
how many moles are in 25.8g of sodium?
1.12 mol
what is the total number of atoms in 2.70 moles of aluminum? (NA= 6.022 x 10^23)
1.63 x 10^24
copper (I) chloride has the following formula
CuCl
what is the correct formula for magnesium permanganate?
Mg(MnO4)2
the empirical formula of a compound is NO2, and its molar mass is about 92.g. what is its molecular formula?
N2O4
of the five elements Na, Al, S, Cl, F, the least electronegative is
Na
which is the correct formula of sodium oxide?
Na2O
which of the following descriptions of a subatomic particle is correct? a) a proton has a positive charge and a mass of approximately 1 amu b) an electron has a negative charge and a mass of approximately 1 amu c) a neutron has no charge and its mass is negligible d) a proton has a positive charge and a negligible mass e) a neutron has a positive charge and a mass of approximately 1 amu
a) a proton has a positive charge and a mass of approximately 1 amu
the ionization energy of rubidium is less than the ionization energy for a) cesium b) sodium c) potassium d) lithium e) fluorine
a) cesium
which of the following is an example of a physical change? a) grinding paper b) burning a candle c) converting hydrogen and oxygen to water d) digesting a hot dog e) frying an egg
a) grinding pepper
which of the following is a compound? a) limestone b) astatine c) lithium d) gold
a) limestone
which of the following polyatomic ions has a 3- ionic charge? a) phosphate b) nitrate c) sulfate d) hydroxide e) bicarbonate
a) phosphate
which of the following is an example of a heterogenous mixture? a) water mixed with oil b) salt dissolved in water c) air d) coffee e) vinegar
a) water mixed with oil
the elements in the group 2A of the periodic table are known as
alkaline earth metals
name the Al2O3
aluminum oxide
a hydrogen bond is
an attraction between a hydrogen atom attached to N,O, or F and an N,O or F atom
which of the following measurements has seven significant figures? a) 48007 mi b) 0.05000000 mL c) 60,1040 ton d) 0.0000003 cm
b) 0.5000000 mL
when 22.0g NaCl and 21.0g H2SO4 are mixed and react according to the equation below, which is the limiting reagent? 2NaCl + H2SO4 -> Na2SO4 + 2HCl a) NaCl b) H2SO4 c) Na2SO4 d) no reagent is limiting
b) H2SO4
the reaction of carbon with oxygen to produce carbon monoxide is an example of which class of reaction? 2C + O2 -> 2CO a) single replacement b) double replacement c) combination d) catalytic e) endothermic
b) combination
which of the following is an element? a) salt b) silicon c) ammonia d) carbon monoxide
b) silicon
the mass of a table is actually 12.78kg. a student makes several measurements to determine the mass of the table. which of the following measurements is the most accurate? a) 13kg b) 12.70 kg c) 12.80 kg d) 12.90 kg
c) 12.80 kg
given the 20 electrons, 20 protons, and 20 neutrons in one of which atoms? a) chlorine-37 b) rubidium-85 c) calcium-20 d) chlorine-35
c) calcium-20
which of the following is not a chemical? a) salt b) water c) light d) carbon dioxide e) sugar
c) light
which of the following is a chemical property? a) water boils below 100°c on top of a mountain b) lead is denser than aluminum c) oxygen gas supports combustion d) nitrogen is a gas at room temperature
c) oxygen gas supports combustion
water, H2O, is an example of a(n)
chemical
the chemical name for ClO3 - is "chlorate ion". therefore, the name of HClO3 is
chloric acid
condensation refers to which conversion? a) solid to gas b) liquid to gas c) solid to liquid d) gas to liquid
d) gas to liquid
which of the following masses has the highest precision? a) 900.075 b) 8400.00 c) 68.0088 d) 0.00004
d). 0.00004
as you rise higher in earths atmosphere, the atmospheric pressure
decreases
the following reaction can be energetically classified as 4NH3 + 5O2 -> 4NO + 6H2O ∆H= -906kj
exothermic
the main interactions (intermolecular forces) between molecules of ammonia, NH3, are
hydrogen bonds
the difference in electronegativity between potassium and oxygen is 2.7. what type of bond is expected in the compound K2O?
ionic
the number of valence electrons found in an atom of group A element is equal to
its group number
the atomic mass of an element is equal to
its mass number
what unit of temperature is used in gas law calculations?
kelvin
the first step in the scientific method is
making observations
the molarity (M) of a solution refers to
moles of solute/ L of solution
what is the formula for converting m/s to mph?
multiple the m/s by 2.237
the mass number of an atom can be calculated from the
number of protons plus neutrons
you notice that there is more traffic between 8 and 9 in the morning. this would be a(n)
observation
sulfur is a ______ block element.
p
avogadros number is the number of
particles in 1 mol of a substance
if the electronegativity difference between elements X and Y is 2.1, the bond between the elements X-Y is
polar covalent
semiconductors are located in the periodic table on (or in) the
right side of the table
the element in this list with chemical properties similar to potassium is
sodium
a heating curve illustrates
the chemical changes that occur as the substances is heated
according to the kinetic molecular theory of gases, a gas can be compressed much more than a liquid or solid because
the particles of a gas are very far apart
in an electron-dot structure of an element, the dots are used to represent
the valence electrons
compounds are pure substances that by definition consist of
two or more elements in combination
the measurement of the gravitational pull on an object is its
weight