CHEM 1010 chapter 2
What is a catalyst?
A substance that increases the speed of a reaction
Orange
Air has become unhealthy for some groups
Which two pollutants are responsible for the production of ozone in the troposphere?
-Volatile organic compounds -nitrogen dioxide
Provide the proper coefficients (including 1's) required to balance this reaction: H2+O2 -> H2O
2H2 + 1O2 = 2H2O
Prop
3 carbons
Incomplete combustion
CO2, H2O & CO
Carbon Monoxide
Colorless, tasteless, & odorless, the silent killer
Pollution Prevention Act
Focused on prevention of formation of hazardous substances
(g)
Gas
What products may be formed when a hydrocarbon undergoes combustion
Heat, CO2, CO
Which of the following options correctly describe ozone exposure and its effects?
Ozone reduces lung function Ozone reacts with the rubber on car tires
Rank the pollutants from the most to the least toxic, based on the values given in the accompanying table. Be careful; note that these numbers are the concentration levels deemed unsafe. Start with the most toxic pollutant at the top of the list.
PM2.5, O3, CO
Basements
Radon
Sulfur dioxide
Sharp, unpleasant odor; produced by burning coal
(l)
Liquid
Rainy, windy weather
Lower O3 levels
CH4
Methane
For low concentrations, it is more convenient to use units of parts per ___, instead of percent. This unit is of a concentration 10,000 times smaller than 1%
Million
Air
Mixture
Hepta
7
Which of the following options correctly describe the symbols used to write a balanced equation?
The symbol (g) indicates a substance in the gas phase. A pure liquid is indicated by the symbol (l)
Nail polish remover containing acetone was spilled in a room 7.8 m × 3.6 m × 2.5 m. Measurements indicated that 5,600 mg of acetone evaporated. Calculate the acetone concentration in micrograms per cubic meter.
7.8 m×3.6 m×2.5 m=70 m3 5600*(1000ug/1mg)*(1/70m3)= 8.0*10^4 ug/m3
Element
Contains only one type of atom
Mixture
a physical combination of two or more substances
A species capable of causing cancer is called a ___ compound
carcinogenic
Which of the following pollutants have strong enough lifetimes that their concentration indoors is much lower than outdoors
O3, NO2, SO2
Which of the following statements correctly describe radon? Select all that apply.
- radon is chemically unreactive -radon can be found in basements -radon is radioactive.
tobacco smoke- paints and varnishes- basements- ventilation systems-
-formaldehyde, benzene - VOCs -radon -O3, NO2, SO2, CO
Which of the following activities do NOT cause indoor air pollution? Select all that apply.
-turning on the television -running the washing machine
The air exhaled from the lungs of a smoker has a concentration of 25 ppm CO. Express the concentration as a percent
0.0025%
Calculate the volume of air in liters that you might inhale (and exhale) in 1.0 hour. Assume that each breath has a volume of 0.31 liters, and that you are breathing 11 times a minute
0.31*11= 3.41 3.41*60= 204.6 204.6*1= 204.6 204.6 L
Mono
1
Meth
1 carbon atom
How many carbon atoms does this hydrocarbon contain: decane
10
Megacities contain ___ people or more
10 million
Megacities contain _____ people or more.
10 million
micro
1x10^-6
Di
2
Eth
2 carbons
A sample of cigarette smoke contains 2.12% carbon monoxide. The U.S. national ambient air quality standard for CO in a 1−hr period is 35 ppm. How many times greater than this standard is the CO concentration in cigarette smoke?
2.12%*(1pph/1%)= 2.12pph 2.12pph = (1,000,000ppm/100pph)= 21,200ppm The NAAQS for CO in a 1−hour period is 35 ppm. 2.12pph*(1/1%)*(1,000,000ppm/100pph)*(1/35ppm)=606
Penta
5
Hexa
6
Which of the following options correctly describe the troposphere
75% of our air is found within the troposphere The troposphere is the region of the atmosphere in which humans live An inversion layer in the troposphere occurs when cooler air is trapped below warm air
Express this concentration in terms of ppm: 0.0075%
75ppm
Which of the following actions are permitted in balancing a chemical equation?
Adding coefficients to formulas of reactants and products. Multiplying all coefficients by a common factor.
"Sick building syndrome" may result from
Air filters that are not maintained, buildings with poor ventilation
Red, purple or maroon
Air is unhealthy for everyone to breathe
Green or yellow
Air quality is good to moderate
Balance the unbalanced equation given and match each substance to the correct coefficient as indicated. Al(s)+O2(g)=Al2O3(s)
Al= 4 O2= 3 Al2O3= 2
Which of the following options correctly describe air pollutants?
All air pollutants are hazardous at levels well below 1 ppm. Particulate matter is an example of an air pollutant
NH3
Ammonia
The smallest unit of an element that can exist as a stable independent entity is a(n)
Atom
A molecule is an independent structure composed of two or more ____ chemically bonded together.
Atoms
Identify the coefficients required to balance the chemical equation C4H10(g)+O2(g)= CO2(g)+H2O(g) correctly.
C4H10= 2 O2= 13 CO2= 8 H2O= 10
Complete combustion
CO2 & H2O
Volatile organic compounds (VOCs) are ____ containing compounds that pass easily into the ____ phase
Carbon; vapor
What ailment is the primary hazard associated with exposure to particulate matter
Cardiovascular disease
Nitrogen dioxide
Characteristic brown color; emitted from car engines
The correct formula for the compound dichlorine pentoxide is Cl_O_. Enter your answer in the correct format
Cl2O5
Particulate matter
Classified by size rather than composition
Compound
Consists of two or more elements, chemically bound
Which of the following options correctly describe particulate matter
Dust is an example of particulate matter Particulate matter can originate from fires, car engines or coal burning plants Some particulate matter can pass into the bloodstream and cause heart disease
US Clean Air Act
Established air quality standards; focused on limiting exposure to hazardous substances
The risks presented by pollutants are a function of toxicity and ____, the amount of a substance encountered
Exposure
True or false: In order to balance the reaction of hydrogen gas (H2) with oxygen gas (O2) to form liquid H2O a student adds a subscript of 2 to the oxygen in H2O. This is an acceptable method of balancing the above reaction.
False
True or false: if an AQI value is reported at 93 this indicates that the sum of the pollutants present gives an AQI value of 93.
False
Pure substance
Form of matter with a definite composition
Tobacco smoke
Formaldehyde, benzene
A chemical ____ represents the elementary composition of any pure substance
Formula
Hydrocarbons are primarily used as
Fuel
The set of principles used to design environmentally friendly chemical products and/or processes is called ___ chemistry
Green
Sunny days
Higher O3 Levels
Which of the following statements correctly describe the information gained from a balanced chemical equation?
Identities of substances involved Relative quantities of substances involved Often the physical states of reactants and products
Which of the following cities are megacities? (Select all that apply.)
Istanbul Delhi Beijing Moscow Sao Paulo
Which compound reacts with ozone, reducing the ozone concentrations along congested highways
NO
Which of the following pollutants are generally produced by the majority of cars
Nitrogen oxides, carbon monoxide, VOCs
Which of the following are toxic gaseous pollutants that may be found in air?
O3, SO2, CO
A molecule that always contains carbon and may contain hydrogen, oxygen and nitrogen is called a(n) ___ compound
Organic
Compounds that are made up of only hydrogen and carbon are called
Organic
O3
Ozone
Which noble gas is the second leading cause of lung cancer after cigarette smoke
Radon
Combustion is an example of a type of chemical ___, where reactants are transformed into products
Reaction
In the process of ____, the foods that we eat are metabolized to produce carbon dioxide, water and energy
Respiration
The process of evaluating scientific data and making predictions in an organized manner about the probabilities of an outcome is called ___ assessment
Risk
Give the correct chemical formula for sulfur tetraflouride. Do not use any special formatting.
SF4
Which of the following statements correctly describes the sources & environmental effects of SO2 (sulfur dioxide)
SO2 can react with water to produce acid rain SO2 can lead to the formation of aerosols
Ozone
Sharp odor; a pollutant in the immediate atmosphere but essential at high altitudes
Which of the following options correctly describe the factors that affect air quality
The number of people living in a region affects air quality. Weather patterns have an affect on air quality
What term is used to describe a situation where a resource is no particular groups responsibility but if it is destroyed or overused this has consequences for a large number of people
Tragedy of commons
Paints & Varnishes
VOCs
Is the chemical equation depicted in the illustration balanced? Why?
Yes the chemical equation is balanced. There are the same number and type of atoms on each side of the chemical equation.
A carcinogenic compound is one that causes _____.
cancer
Sustainability is correctly defined as _____.
meeting present needs without compromising the ability of future generations to do the same
Managing human consumption of natural resources so that these resources are not exhausted is called _____.
sustainability
When naming a compound of two nonmetals, the number of ____ of each element is indicated by a Greek numerical prefix. The first element in the name is numbered only when more than ___ atom(s) of that element is/are present.
Atoms; one
ppm
1 part/1x10^6 parts
ppb
1 part/1x10^9 parts
Atmospheric nitrogen reacts with atmospheric oxygen to form nitrogen monoxide. Which of the following is the correct balanced equation for this process?
N2(g)+O2(g)=2NO(g)
Consider the list of gases shown below. Select those you would expect to find coming directly from a vehicle's tailpipe. N2 CO O3 NO CO2 SO2
N2, CO, O3, CO2, SO2
Provide the correct name for the following molecular compound: NO
Nitric oxide
Which of the following options correctly describe N2
Nitrogen is colorless & odorless Nitrogen is the most abundant substance in air
Place the gases that make up air in order of decreasing percent composition, starting with the most abundant gas at the top of the list.
Nitrogen, oxygen, argon
Equal volumes of molecular gases always contain the same ___ of gas molecules at the same temp and pressue
Number
Which of the following options correctly describe the characteristics & role of oxygen
O2 is absorbed into our blood via the lungs O2 is a necessary reactant in burning & rusting Oxygen atoms are the most abundant atoms by mass in the human body
Ventilation systems
O3, NO2, SO2, CO
Which of the following are examples of mixtures?
Soil, tap water
(s)
Solid
A chemical equation is a statement using chemical ___ that expresses both the identities and the relative ___ of the reactants and products involved in a chemical or physical charge
Symbols; quantity
Which of the following are examples of shifting baselines?
The Internet is accepted as a normal way of life People in technological cultures no longer remember life without electric lighting
What term is used to describe the intrinsic health hazard of a substance
Toxicity
Place the layers of Earths atmosphere in the correct order, starting with the layer that is closest to Earth at the top of the list
Troposphere, stratosphere, mesosphere, thermosphere, exosphere
A species that passes easily from the liquid to the vapor phase is called a(n) ___ substance
Volatile
Which of the following options correctly describe the formation and control of pollutants produced by cars?
Volatile organic compounds are connected to the formation of nitrogen dioxide. Catalytic converters have reduced the CO emissions from cars
H20
Water
Particulate matter with the designation PM10 includes particles with an average diameter of 10 ___or less
um
Which of the following options describe the correct format used when writing the chemical formula of a substance? Select all that apply.
A chemical formula is a symbolic way to represent the composition of a substance The number of atoms of a particular element is indicated by a subscript
Which of the following statements correctly defines a molecule?
A molecule is independent structure consisting of two or more atoms chemically bonded together
Output of carbon ___ is used to measure the efficiency of an automobile. This gas is measured in order to determine the degree of ___ combustion
Monoxide, incomplete
Ozone decomposes into oxygen and atomic oxygen. Which of the following statements correctly describe the balanced equation for this reaction?
O2 is a product of the reaction. There are 3 atoms of oxygen on the left side of the reaction and 3 atoms of oxygen on the product side of the equation.
A(n) ____ pollutant is produced from chemical reactions involving one or more other pollutants.
Secondary
Which of the following options correctly describe aerosols?
Aerosols can contribute to pollution SO3 can combine with water to create sulfuric acid aerosols Aerosols are liquid and solid particles that remain suspended in the air
In a combustion reaction, a hydrocarbon reacts with oxygen to produce carbon dioxide and water. Note that the oxygen found in the reactants ends up in both products. In order to balance the chemical equation in the most efficient manner it is best to balance the oxygen atoms ___
Last
If a compound is composed of nitrogen and hydrogen atoms in a respective one-to-three ratio, what is the correct chemical formula for this compound?
NH3
Place the chemical steps involved in ozone production in the correct order. Place the first step of the process at the top of the list and the last step at the bottom of the list.
Nitrogen dioxide is exposed to sunlight. Nitrogen monoxide and an oxygen atom are produced An oxygen atom reacts with an oxygen molecule Ozone is produced
Rank these substances in order of their abundance in the air you breathe from least abundance to most abundance
O3, CO2, Ar, O2, N2 He, CO2, Ar, O2, N2
Which of the following options correctly describe the characteristics and behavior of argon which is a component of air
Argon is typical component of air Argon makes up less than 1% of air
But
4 carbons
Different forms of the same element (such as O2 & O3) are called
Allotropes
To burn 1 molecule of C3H8 to form CO2 and H2O (complete combustion), how many molecules of O2 are required?
C3H8 + 5 O2 → 3 CO2 + 4 H2O So five molecules of O2 are required.
Oxygen (O2)
Pure substance
What is ambient air
The air surrounding us
True or false: After the completion of a chemical reaction the number of substances many change bu the total mass of matter present remains constant.
True