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Question | Answer |
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scientist believe they know the average global temperature over the last 160,000 years. which property of the ice core samples from antarctica provides the information | the carbon dioxide cocentration |
which atmospheric component does not contribute to global warming | N2 |
what international agreement attempted to reduce greenhouse gas emissions | kyoto protocol |
carbon dioxide is the primary compound discussed with respect to global warming, of the common atmospheric components the global warming potential (GWP) of a carbon dioxide molecule is very low. which statement best explains pair of facts | co2 exists in relativley high concentration |
scientist have correlated average global temperature with atmospheric carbon dioxide levels for the last 160,000 years using cores from antarctica. how is the carbon dioxide level determined | by measuring the Co2 concentration in trapped gases in the ice layers |
where is most of the carbon on earth stoked | in the form of fossil fuels and carbonate minerals and rocks |
the industrial revolution is a key point in the earths atmospheric history | prior to that time deposits of petroleum and coal were not being used as energy sources |
which occurrences or processess are expected to reduce the level of atmospheric carbon | decaying plants and animal,the growth of trees |
carbon cycle refers to | movement of carbon through living organisms, the atmosphere, the sea, and the earth |
characteristics pertain to the problem of global warming | possible consequences include altered climate and increased sea level,increased skin cancer incidence and damage to radiation sensitive species has been observed |
identify the single most effective strategy to reduce carbon dioxide emissions | develop alternate energy sources that do not rely on fossil fuels |
what country has the highest per capita emission of carbon dioxide | united states |
what practices might be described as carbon sequestration | pumping carbon dioxide deep into ocean,increasing combustion of fossil fuels |
process plays the most important role in the greenhouse effect | energy from the sun is absorbed by the atmosphere |
what explanation accounts for the fact that on average cloudy nights are warmer than clear nights | clouds are composed of water vapor and H2O is a strong greenhouse gas |
the greenhouse effect refers to the process by which | greenhouse gases absorb ultraviolet radiation from the sun, warming the molecules |
chloroflurocarbons rise to the strosphere and | after intereacting with uv energy, become free radicals which destroy ozone |
one isotope for a particular element is distinguished from another by the number of | neutrons |
free radicals are | species with unpaired electrons |
frequency is | number of waves passing a fixed point in one second |
what electron accounts for many of the chemical and physical properties | outermost |
single bonds, double bonds, and triple bonds | have 2,4,6, shared electrons |
light behaves like | wave and a particle |
HFCs may be used to replace CFCs, which coupound is a HFC | CH2F2 |
the wavelength of light in the xray region of the electromagnetic spectrum is | about the size of a bacterial cell and virus |
when one pair os shared electrons is involved in a covalent bond, the linkage is called | single bond |
the atomic number is | number off protons in a nucleus |
the periodicity of the properties of elements is cheifly due to the | ___ |
elements iin the same colum of the periodic table have what in common | valence electrons |
isotopes of an element have the same number of | protons, but different numbers of neutrons |
speed of light in air | does not depend on wavelength or frequency |
wavelength | distance between successive peaks of waves in the electromagnetic spectrum |
structure of ozone most closely resembles a | bent molecule with the same length of chemical bonds |
O2 and O3 molecules are | allotropes |
which color in the rainbow has the shortest wavelength | blue |
what forms by cmonining an oxygen atom with an oxygen molecule | ozone |
what is the most energetic of the three forms of Uv light | UV-C |
what is the unit for concentration of ).00004% | pph |
choose the name of the compund formed by combining potassium (K) with iodine (I) | potassium iodide |
what is the compound formed by combining carbon with oxygen | carbon dioxide |
green chemistry is | the design of products and processes that reduce hazardous substances |
pure substance | an element of a compound |
compound | element of a compound made up of two or more |
mixture | physical combinations of two or more substances present in variable amounts |
if representative element "X" reacts with representative element "P" the result is | XP |
what process does not involve a chemical change | bioling water |
matter | anything that has mass and occupies space |
elements consist of 3 categories | metals, non metals, transition |
metals | elements that are shiny and conduct electricity and heat |
nonmetals | elements that cannot be cast into shapes have varied apperances and do not conduct well |
metaloids | 8 elements sometimes called sentimetals, B,SI,GE,AS,SB,TE,Po,At |
noble gases | group 8a.elements that are inert and do not readily undergo chemical reactions. |
atoms | what all matter is composed of super small particles smallest unit of an element that can exist as a stable, independent entity |
molecule | fixed number of atoms held together by chemical bonds in certain spatial arrangement |
electrons | neg charge and is on the outer shell |
protons | positive charge |
neutrons | no charge |
where is the nucleus | center of atom |
combustion | rapid combustion of oxygen with a substance |
chemical reaction | process wherby substances describes as reactants are transformed into different substances called products |
law of conservation of mass and matter | mass is neither created nor destroyed in new substance. |
cataylyst | chemical substance that participates in a chemical reaction and influences its speed with undergoing permanent change |
allotropes | two or more forms of the same element that differ in their chemical structure and therefore in their properties |
atomic number | number of protons in an atom of that element. example: H contains 1 proton,=atomic mass of 1 |
covalent bonds | a chemical nond in which two electons are shared by the atom involved |
atoms | elements are made of |
mono means | 1 |
di or bi | 2 |
tri | 3 |
tetra | 4 |
penta | 5 |
hexa | 6 |
hepta | 7 |
octa | 8 |
nona | 9 |
deca | 10 |
nitrogen monoxide chemical formula | NO |
nitrogen dioxide | NO2 |
hydrocarbsons | compounds of hydrogen and carbon- and can have more than 4 carbon atoms,also called organic compound |
single covalent bond | formed when only one pair of shared electrons forms the linkage bewteen atoms |
octet rulei | fact that electron in many molecules are arranged so that every atom except hydrogen) shares 8 electrons |
polyatomic molecule | consists of 3 or more atoms |
triple bond | is a covalent linkage made up of 3 pairs of shared electrons, short, hard and strong to break. |
% to ppm | 4 decimal places to right |
ppm to % | 4 places to left |
percent by mass or composition | figure each elements molar mass. massof element divided by mass of compound x 100% |
avagadros # | = to 1 mole 6>02 X 10^23 of anything usually molecules to atoms |
molecular weight= | how many moles |
grams to moles you | divide, start with grams |
moles to grams you | multiply start with moles |
infared spectroscopy can determine unknow molecules | _ |
periodic properties | elements are sequenced in order of increasing atomic number, they have similar chemical propterits fall in the same columns |
outer valence electrons | found in the highest energy level and help to account for many of the observed trends in chemical properties |
lewis structure | representation of an atom or molecule that shows its outer electrons |
halons | compunds in which BR and F atoms replace some or all of the clorine atoms |
tetrahedron | four corneded figure with four equal triangular sides |
wavenumber= | 10,000 divided by wavelenght |
diatomics gases | N2 and O2 |
quantized | electronic,vibrational,and rotational energy means only certain energy levels are permitted |
anaerobic bacteria | those that can function without the use of molecular oxygen, produce methane |
albedo | ration of electromagnetic radiation relflected relative to the amount of radiation incident on the surface:is a measure of relectivity of a surface |
what subtomic particles surround the nucleus | electrons orbit in shells |
what does the number of electron in an elements outermost orbital (compared with the toal number possible) determines | its chemical properties and reactivity |