Chem
light travels at a speed of 3.00x108 what is the speed of light in kilometers
1.08x10 9
what is atomic radius of in
166 pm
What is the atomic number for nitrogen atomic number 7
1s2 2s2 2p3
The electron notation for aluminum (an 13) is
1s2 2s2 2p6 3s2 3p1
ultraviolet radiation with a frequency of 1.18x10 15 hz is used to disinfect water. what is the wavelength
2.54x107 m
group _______ in the periodic table contains only metals
2a
how many orbitals in the 4p sublevel
3
the electorn configuration of nirtrgoen is 1s2 2s2 2p3. how many more eletorns does nitrogen need to satisfy the octet rule?
3
what is the number of sig. figs. in the measure 5.00 cubic meters
3 (B)
the electorn configuration of aluminum, (an 13) is (NE) 3s2 3p1 aluminum is in period
3 (answer choice B)
A sample of the element x contains 90 percent 35x atoms 8.0 percent 37 x and 2.0 per2cent 38x atoms. the average atomic mass is closest to
35 amu
if 75.0% of the atoms of an elememt have a mass of 35,0 amu and 25% of the atoms have a mass of 37.0 amu what is the average atomicmass
35.5 amu
In the electron configuration for scandium what is the notation for the three highest energy electrons
3d1 4s2
what is the energy of a quantum of blue light with a wavelength of 460 nm
4.3x10-19 j
a hydrogen lamp emits several lines in the visible region of the electromagnetic spectrum. one of these lines has a wavelnght of 6.56x10-5 cm . what is the frequency of this radiation
4.57x10 14 s-1
how many orbitals are in the 3d sublevel
5
what is the number .0513 expressed in scientific notation
5.13x10-2
a laser poiter emits light that has a wave length of 5.32x10-7 m what is the frequency of the light?
5.64x10 14 hz
which of these observations or values represents an extensive property of the material
500 cm3
The electron configuration for the carbon (c) is 1s2 2s2 2p2. The atomic number of carbon is
6
express in scientific notation and correct sig. figs
6.6x10 4
The number of electrons in the highest energy level of the Argon atom (an 18) is
8
the atomic number of oxygen, 8 indicates that there are
8 protenons in the nucleus of an oxygen atom
what is the volume of a paperback book 21 cm tall, 12 cm wide, and 3.5 cm thick
8.8x10 2 cm3
what is the symbol and meaning of the prefix -mili
;10 -3
A line spectrum is produced when an electron moves from one energy level to
A lower energy level
A chemist who frequently carries out a complex experiment is likely said to have high
Accuracy but low precision
A measurement that closely agrees with accepted values is said to be
Accurate
These values were obtained as the mass of products from the same reaction. 8.83 g, 8.84 g, 8.82 g. The known mass of products from that reatction is 8.6 g these values are
Accurate
A measurement is said to have good precision if it
Agrees closely with other measures of the same quantity
The attractive forces ina liquid
Are too weak to hold the particles in fixed positions
What concept in daltons atomic theory has been modified
Atoms cannot be divided
Poor precision in scientific measurement may arise from
Both human error and the limitation of measuring instrument
what is the formula for the compound formed by calcium ions and chloride ions
CaCl2
Precision pertains to all the following except
Closeness of a measurement to accepted value
The change of an atom from an excited to ground state always requires
Emission of electromagnetic radiation
One of the wave properties of electromagnetic radiation , such as light, is
Frequency
Compared with gases solids are
Incompressable
As the atomic number increases, the number of electrons in an atom
Increases
If electro radiation a has a lower frequency then electro magnetic radiation b then compared to the wavelength of b, a is
Longer
Atoms of the same element can differs in
Mass number
the total number of protens and neutrons in the nucleus of an atom is its
Mass number
Compared with the particles in a gas, the particles in a liquid
Move around less
If the s and p orbitals of the highest main energy level of an atom are filled with electrons then the atom has an
Octet
which are chemical symbols for lead, oxygen, and siver?
Pb,o,Ag
Mendeleev is credited woth developing the first sicessful
Periodic table
Using the same balance, a chemist obtained the values 5.224g 5.235 g, and 5.25 g for the mass of a sample. These measurements have
Poor precision
Which of the following observations is qualitative
Salt deposits form from an evaporated liquid
The element with electron configuration 1s2 2s2 2p6 3s2 3p2
Si (z=14)
If electrons in an atom have the lowest possible energies then the atom is in
The ground state
Which of the follwoing observstions is quantitiative
The liquid boils at 100 celcius
Which of the following is not part of daltons atomic theory
The number of protons in an atom is its atomic number
What. Causes the high density of solids
The particles are packed closely together
Particles within a solid
Vibrate weekly about fixed positions
The distance between two successive peaks on a wave is its
Wavelength
what is the formula for zinc flouride
Znf2
The homogenous mixture in the illustration above is in container
a
which statement describes a physical change?
a sculptor casts a statue in molten bronze and allows it to harden
the group of soft silvery active metals, all of which have one electron in an s orbital is known as
alkali metals
what info is often included in the a periodic table
all of the above
why do all samples of a given substance have the same intneisve prop?
all the same have the same chemical composition
the most characteristic property of noble gases is that they
are largely unreactive
a positive ion is known as
cation
The electrostatic attraction bwteen positively chargerd nuclei and negatively chargerd eectrons permits 2 atoms to be held together by a
chemical bond
which of the following is an intensive physical property
color
how are compounds different from elements
compounds can be broken down by chemical menas into simpler substacnes, but eements cannot
the principles of atomic theory recognized today were conceived by
dalton
from left to right across a period of the periodic table. atomic radius tends to
decrease
from top to bottom within a group, first ionization energy starts to
decrease
which of the following is a physical prop of a substance in the liquid state
definite volume
a student observes a cack in a test tube that is used for a lab. what should the student do with the test tube
dispose of it in designated area
experiments with cathode rays lead to the discovery of
electron
what subatomic particle plays the greatest role in determining the properties of an element
electron
which of the following is a physical change
evaportation
which row of the periodic table corresponds to a hazard relted tot he material
flammability
energiesacross a period in the periodic table atomic radii
gradualay decrease
which groups in the main group have lower electronegaitivity thand d block element
groups 1 and 2
hydrogen is placed seperratly from other elements in the periodic table because it
has many unique properties
in the alkali earth group atoms with the smallest radii
have the highest ioization energies
chemical properties
include changes that alter the identity of a substance
what are two categories used to classify properties of matter
intensive and extensive prop.
helium-4 helium-3 are
isotopes
how many electrons will calcium atom gain or loose in forming an ion
it will loose 2
which of the following is the correct name for pb02
lead (4) oxide
matter inludes all the following except
light
The state of matter in which a material has a definite volume but no definite shape is the
liquid state
the comprssibiliy of solids is generally
lower than the compresssiblity of liquds and gases
an example of an extensive physical property is
mass
two features that distinguish matter are
mass and volume
isotopes are atoms of the same element that have different
massses
upon a completion of laoraeory inversigations, where should students return all materials
materials should be returned to the teacher designated location
a physical property may be investgated by
melting ice
the elements that border the zig zag line in the periodic table are
metalliods
what are the three broad classes of elements
metasl, nonmetals, metallkiods
physical means can be used to seperate
mixtures
The average atomic mass of an elemnt is the aerage of the atomic masses of its
naturally occurring isotopes
what category does an element beling if it is a poor conductor of electricity
nonmetals
a student spills a small amount of acid on the table, what should the student do first?
notify his/her lab partner and the teacher
the periodic law states that the hysicala dnc ehmcial propertyies of elements are periodic fucntions of their atommic
numbers
Mendeleevs table was called the periodic table because the properties of elements
occured at repeated intervals called periods
which is an acceptable way to protect your eyes in the chemistry laboratory
only by wearing chemical safety googles
The electron configurations of the noble gases from neon to radon in the periodic table end with filled
p orbitals
a horizontal row on the periodic table is usually refreed to as a
period
which has larger ionization enegy, magnesium or phsphorus
phosphorus
a sheet of paper is torn into several small pieces. what type of change happened to the paper?
physical change only
zoe observes water bubbling. she measures the temp. of the water to be 373 k. observing a chemical or physical change
physical change; 373 is boiling point of water
each period in the periodic table corresponds to a
principal energy level
which of these entrie refers to a chemical property of methanol?
products of combustion
ekemnts in a group or colum in the periodic table can be expected to have simila
properties
one chemical property of matter
reactivity
the average atomic mass of an element depends on both the masses of its isotopes and each isotope's
relative abundnace
the variable that is observed during an experiment is called what type
responding
is the freezing of mercury revirsable or irrevirsable change?
reversible because solid mercury can be melted to form liquid mercury again
in group 2a elements the valance elctrons are in sublevel
s
compared with nonmetals the number of valance electrons in metals is generally
smaller
what is the name of NaCl
sodium chloride
the state of matter in which particles are rigidly held in fixed positions is the
solid state
what are the 3 main states of matter
solid, liquid, gas
what procedure should be used to put out a fire ata lab station that is fueled by flammable liquids?
spay with carbon dioide or drychemical
the substances that are chemically bound together are
the elements that compose water
a chemist mixes liquid substance x and solid sunstnce y in a beaker, then stirs the mixture vigourously. which observation or measurement would provide the strongest evidence that the two substances have undergone a physical, but not chemical change
the mixture can be separated into two substances one with the same melting point as substance x and the other with the same melting point as substance y
isotopes of each element differ in
the number of neutrons in the nucleus
what equals the speed of a wave
the product of wavelength and frequency
what can you conclude about the properties of alkali metals
they are highly reactive
which is not a property of metals
unreactivity
under ordinary conditions of temperature and pressure, the particles in gas are
very far from eachother
how does visible light differ from radio waves, microwaves, and the other components of the electronmagnetic spectrum
visible light has a different range of frequencies and wavelengths
a list of substances could include
vitamin c (ascorbic acid)
in rutherfords experiments positively charged particles
were used to bombart thin metal foil