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May 24, 2015

Search: How many oxygen atoms are in 2.90g of quartz?

Number of results: 5,976

Science Easy 2 Points!
Which of the following best explains why it is nessecary for the body to eliminate waste? a) to allow the body to maintain a certain size b) to keep the body's internal enviroment in balance c) to make room for nutrients coming in d) to reduce unpleasent odors What happens to ...
December 12, 2013 by Billabong

Chemistry
According to the ideal gas law a 9.03 sample of oxygen gas in a 0.8112 container at 499k should exert a pressure of 456atm. By what % does the pressure calculated using van der waals equation differ from the ideal pressure? For O2 gas a=1.36 L^2atm/mol2 and b=3.18e-2 Hint: %...
January 14, 2012 by Hannah

chem
Can someone help me with these please? 1) Use water as an example to contrast the properties of a compound with the elements from which it is composed. 2) If you tried to breath carbon dioxide, you would suffocate. Why, then, is carbon dioxide essential to all life on Earth? ...
January 11, 2007 by June

sience plz hep
1. Which layer of the sun's atmosphere are you looking at when you look at an image of a sun? A) Photosphere B) Chromosphere C) Corona D) Prominence 2. What materials could have been found in a giant cloud that formed the solar system? A- hydrogen and helium B- hydrogen and ...
April 7, 2015 by bmx

PHYSICS
When a conducting sphere is charged positively, initially the charge is deposited on the left side. However, due to the sphere's conducting nature, the charge spreads uniformly throughout the surface to the sphere. Charge is uniformly distributed because: A. charged atoms at ...
April 8, 2009 by sophie

Science (Chemistry)
I did not understand the lesson today in my Chemistry I honors class. We went over the Law of Conservation of Mass for roughly 15 minutes and he gave us this worksheet. Could someone please display how to do this, I'll pull a problem from the worksheet. When 9.56g of Copper ...
October 7, 2009 by Michael Glass

CHEM
I was just wondering if someone would be able to critique my answers for the following Chem questions? they range from pretty basic to a bit more... 2)which of the following is the definition of the value of Avogadro's constant: b) the # of Carbon atoms in exactly 12g of ...
October 21, 2007 by K

General Chemistry
Balance the following redox reaction in acidic and basic solutions: Fe(OH)2(s) + O2(g) --> Fe(OH)3(s) These are the steps my instructor gave us to balance redox reactions: 1. Divide into 1/2 rxns (reduction & oxidation) 2. Balance atoms other than H & O 3. Balance O with ...
April 3, 2013 by Emily

Chemistry
The complete combustion of 0.100 mol of CH4 in oxygen in a bomb calorimeter caused the water of the calorimeter to rise in temperature from 25.00 degrees Celsius to 37.70 degrees Celsius. Suppose that the combustion of the 0.1 mol of CH4 was instead run at constant pressure (1...
February 6, 2009 by HELP!!!

honors chemistry- isotopes...
can scientists actually measure the mass and relative abundance of isotopes of an element by counting each particle and measuring their masses? [ i think no because it would be too small ] if not, how could a scientist measure the mass and relative abundance of isotopes of an ...
October 31, 2006 by guitarking4000

Chemistry
Consider a fuel cell that uses the reaction of ethanol with oxygen to produce electricity, CH3CH20H(l)+ 3O2(g)---> 2CO2(g)+3H2O Use thermodynamic data to determine the value of E°cell for this cell at 25 °C. I don't really know where to start. I got the standard G for ...
May 5, 2014 by Sophie

Chemistry
The reaction for the decomposition of dinitrogen monoxide gas to form an oxygen radical is: N2O(g)==>N2(g)+O(g) . If the activation energy is 250 kJ/mol and the frequency factor is 8.0 x 1011 s-1, what is the rate constant for the first-order reaction at 1000 K? k = A * exp...
March 1, 2010 by gaby

science
Where does the exchange of carbon dioxide and oxygen with the blood occur the bronchi bronchiole alveolar ducts alveolar sacs It seems that you are asking different questions under different names. You can ask more than one question on a post. Think of it as transportation. ...
May 19, 2007 by dimples

chemistry
Based on the mass of O2 produced can you calculate the gram molecular weight? Chem lab on oxygen production 10g KClO3 reacts with heat to produce 2KCl(s)+3O2.What is the mass produced? 10g/122.6=0.0816 mole of KClO3 0.00816x3moleO2/2moleKClO3=0.1224 moleO2 0.1224 molex32g O2/...
October 18, 2010 by michelle

science ms sue plz help
1. Which layer of the sun's atmosphere are you looking at when you look at an image of a sun? A) Photosphere B) Chromosphere C) Corona D) Prominence 2. What materials could have been found in a giant cloud that formed the solar system? A- hydrogen and helium B- hydrogen and ...
April 10, 2015 by need help plz

AP CHEMISTRY
A)In a chemical reaction two gases combine to form a solid. What do you expect for the sign of ΔS? B) For which of the following processes does the entropy of the system increase? (Select all that apply.) -> alignment of iron filings in a magnetic field -> the ...
March 19, 2012 by HELP PLEASE

Plz, Ms.Sue/anyone check my answers?
1. Which of the following best explains why it is necessary for the body to eliminate waste? to allow the body to maintain a certain size to keep the body’s internal environment in balance to make room for nutrients coming in *** to reduce unpleasant odors 2. What happens to ...
May 13, 2014 by Princess Anna

chemistry
1. Ceramic material made by the sol-gel process involve the reaction of a. water and acids. b. ethanol and water. c. water and metal oxides. d. acids and metal alkoxides. e. water and metal alkoxides. my ans. c 2. The step in the sol-gel process that forms oxygen bridges while...
December 2, 2012 by 657

Chemistry
can anyone check and see if i balanced the equation for the combustion of benzene correctly, thank you. C6H6 + O2 --> CO2 + H2O Answer: C6H6 + 15O2 --> 6CO2 + 3H2O It doesn't look right to me; however, you can check ALL balanced(?) equations and know when you are right ...
August 7, 2007 by Anonymous

chemistry
sulfur trioxide gas dissociates into sulfer dioxide gas and oxygen gas at 1250 degrees C. In an experiment, 3.6 moles of sulfur trioxide were placed into an evacuated 3.0-L flask. THe concentration of sulfur dioxide gas measured at equilibrium was found to be 0.20 M. What is ...
April 29, 2007 by alexa

Chem
Butane, C4H10, is widely used as a fuel for disposable lighters. When one mole of butane is burned in oxygen, carbon dioxide and steam are formed and 2658 kJ of heat is evolved. a) Write the thermochemical equation for the reaction. First I wrote the chemical equation for the ...
February 1, 2007 by Chris

chemistry
Compound B is acetylcholine, a neurotransmitter found in the human body. It binds to receptors, leading to nerve stimulation. (in case this post does not show correct, two of the CH3 should be above and below the N^+ , AND THE O should be above the C) COMPOUND B CH3 O | | H3C...
January 29, 2009 by trigger

chem
If one pound (454g) of hexane combusts with 185 grams of oxygen which reactant is the limiting reactant and how many grams of carbon dioxide are produced? My work: 454 g C6H14 * 1 mol C6H14/86.18 g C6H14 * 6 mol CO2/ 1 mol C6H14 * 44 g C02/ 1 mol CO2= 1390.7 g/ CO2 185 g O2 * ...
April 1, 2015 by Sarah

Environmental Science
I need a little help on these, i've posted them a few times but i don't get any answers. 29. A common feature of thermal pollution and artificial eutrophication is that they both a. have sources that are difficult to identify and control b. cause large mats of algae to bloom ...
February 8, 2010 by y912f

chem
How would i found out the freezing point of a solution which has 0.05mol of acetic acid dissolved into 125g of benzene? Benzene melts at 5.5C and has a constant of 5.1C/m. The acid forms a dimer (what is this and how does it affect the calculations?) A dimer is a molecule from...
August 7, 2007 by Chris

kim
a gaseous hydrocarbon reacts completely with oxygen gas to form carbon dioxide and water vapor. given the following data, determine (delta)HoF for hydrocarbon: (delta)Horxn=-2044.5kj/mol hydrocarbon (delta)HoF CO2= -393.5kj/mol (delta)HoF H2O = -242kj/mol denstity of CO2 and ...
April 20, 2008 by chemistry

Chemistry
I am having so much trouble understanding how to classify reactions as precipitation, acid base, or oxidation reduction. In one example in particular, it reads Iron II oxide reacts with oxygen and water to yield Iron III hydroxide. I wrote out the equation as: FeO(aq)+O2(g)+...
April 21, 2015 by Tracey

CHEMISTRY
Hello, I am having trouble balancing this redox reaction WITHOUT using the half-reaction method. I believe this is because not all of the elements are in (aq). BrO3-(aq) + N2H4(g) --> Br-(aq) + N2(g) Br is reduced by a factor of 6. N is oxidized by a factor of 2. I will ...
April 21, 2010 by Vanessa

physics
what is thermal equilibrim, and what is thermal energy? what are fluid molecules? does convectin involve the movement of matter in a circular manner only? thermal equilibrium: no net flow of heat in or out. thermal energy: The sum of all the interanal stored energy in the ...
January 29, 2007 by minerva

gravimetric prob
A pure organic compound weighing 947.4mg was heated in a stream of oxygen. The effluent gas was swept successively through a tube of magnesium perchlorate dessicant weighing 18.6137g and a tube of Ascarite weighing 16.8425g. After several minutes the tubes were sealed and ...
April 20, 2015 by vivian

chemistry
The complete combustion of salicylic acid releases 21.90 kJ of energy per gram of salicylic acid. In a particular bomb calorimeter (initially at room temperature), the combustion of 0.1182 g of salicylic acid, in the presence of excess oxygen, causes the temperature of the ...
September 25, 2014 by korko

Physical Education
1. Aerobic activities can be done for an extended period of time and supply oxygen to your muscles. Such activities help develop _______________________. 2. You can change your _______________________ by exercising regularly and eating healthfully. 3. The ...
February 23, 2012 by Maddie

chemistry URGENT...30 min left
Gasoline is a mixture of hydrocarbons of various chain lengths, ranging from 5-carbon chains to 10-carbon chains. One of the hydrocarbons we often hear about is the 8-carbon chain, octane. Octane combusts with oxygen as given by the balanced equation: 2C8H18(g) + 25O2(g) &#...
April 22, 2010 by Luda

Science~!
What would happen to a object if the force of gravity on earth was decreased by half? A. mass would decrease b. its weight would decrease c its density would decrease d. its volume will decrease A certain object has a volume of 25.0 mL and mass of 100g whats the density of the...
December 10, 2014 by becky

Physics 2 College Level
A cylinder is closed at both ends and has insulating walls. It is divided into two compartments by an insulating piston that is perpendicular to the axis of the cylinder as shown in Figure a. Each compartment contains 1.00 mol of oxygen that behaves as an ideal gas with γ...
September 17, 2013 by Sarah

Biology
1. A theory and a hypothesis are different in that: A. you must have a theory before you can form a hypothesis. B. a theory is developed as a result of broad agreement among scientists and a hypothesis is a much less substantiated idea. C. a theory is much easier to disprove ...
July 10, 2013 by Amy

Physics-not sure how to find the charge q
Posted by ~christina~ on Sunday, March 30, 2008 at 9:14am. Two small silver spheres with a mass of 10.0g, are seperated by 1.00m. Calcuate the fraction of the electrons in one sphere that must be transfered to the other to produce an attractive force of 1.00x10^4 N (about 1 ...
April 2, 2008 by ~christina~

Chemistry
1. Which of the following compounds is an unsaturated hydrocarbon? methane *propyne nonane methyl 2. The general name for hydrocarbons with at least one triple covalent bond is ____. alkenes alkyls alkanes *alkynes 3. What is the name of the smallest alkyne? butyne *ethyne ...
April 11, 2013 by Cassie

Chemistry
For fluoracetic acid the highest Boltzmann distribution is when the dihedral angle is at 0 degrees. However, going from chloro- to bromoacetic acid, an increasing dip in the Boltzmann distribution occurs at 0 degrees. What is responsible for this "dip?" (HINT: look at how the...
July 12, 2010 by Anth

chemistry
These are short and simple. :) I've included my answers, tell me if I am wrong please. CH3 is attached to a carbon on a pentane ring. Is the hybridization of the carbon sp3? NH connects a benzene ring to two benzene rings. Is the hybridization of the nitrogen sp2? OH is ...
March 16, 2011 by s

chemistry
These are short and simple. :) I've included my answers, tell me if I am wrong please. CH3 is attached to a carbon on a pentane ring. Is the hybridization of the carbon sp3? NH connects a benzene ring to two benzene rings. Is the hybridization of the nitrogen sp2? OH is ...
March 16, 2011 by s

chemistry
Hello, ((((((I need the answer in a hour from my posting))))) I have been posting this problme for four days ago, so please show Sympathy. I solved it but I want to be 100% su ...there is moreshow problem Hello, ((((((I need the answer in a hour from my posting))))) I have ...
November 5, 2009 by Cheimie

chemistry
The complete combustion of salicylic acid releases 21.90 kJ of energy per gram of salicylic acid. In a particular bomb calorimeter (initially at room temperature), the combustion of 0.1182 g of salicylic acid, in the presence of excess oxygen, causes the temperature of the ...
September 27, 2014 by korko

Soil Chemistry
In saturated soils, oxygen is quickly depleted and microbes must utilize the next most favorable electron acceptor, in this case sulfate (SO42-). Under these conditions, Mn (and Fe) are oxidized to Mn2+ (and Fe2+). Select the correct oxidation and reduction pair for Mn. A. ...
June 30, 2014 by John

Science/Chemistry
Write a Balanced equation for the chemcial reaction Acetylene gas (C2H2) burns in a welding torch with oxygen to form carbon dioxide gas and water vapor. C2H2(g) + O2(g) ==> CO2(g) + H2O(g) It isn't balanced. I will leave that for you. How do i balance it? trial and error. ...
March 15, 2007 by Chris

Chemistry
I was given a question on an assignment and I can't figure it out. The question is A student collects 90ml of oxygen gas over water at 25c and a total pressure of 99.3kPa from the decomposition of KClO3. 2KClO3(s)-> 2KCl(s)+ 3O2 a) How many mols of O2 were collected? b)How ...
March 6, 2010 by Krissy

Fluid Mechanics
A small rocket motor, fueled with hydrogen and oxygen, is tested on a thrust stand at a simulated altitude of 10 km. The motor is operated at chamber stagnation conditions of 1500 K and 8.0 MPa (gage). The combustion product is water vapor, which may be treated as an ideal gas...
March 22, 2009 by Katie

Engineering
In the process of electrolysis, electrical power is used to separate water into oxygen and hydrogen molecules via the reaction: H2O --> H2 + ½O2 This is very much like running a hydrogen fuel cell in reverse. We assume that only the activation potential for the ...
December 15, 2013 by A

Chemistry
In chemistry lab we did an experiment trying to find the empirical formula of an oxide and tin. The question is "suppose some of the oxide splattered out of the crucible. How would this affect your calculated ratio of the number of moles of oxygen to the number of moles of tin...
November 3, 2010 by Bee

Chemistry
Describe the spectrum of the light from a fluorescent lamp and from an incandescent (tungsten filament) lamp, and try to explain what you observe. So fluorescent lamps use electricity to excite mercury vapour, and the excited atoms produce short-wave UV light which causes a ...
December 5, 2010 by Jon

chemistry
2. 0.300 kilogram chloroform(chlorine calcium3)and 21.0grams eucalyptol(carbon10 hydrogen18 oxygen 3. what is the concentration of a solution of sodium chlorine water containing 1.170grams solute in 100moles solution 4, what is the % by volume of a solution containing 30....
September 14, 2010 by juzen

chemistry
You are a chemist requested to review and analyse certain debris found on thebottom of aboot found in a crime scene. The debris contains metal fragments. If you identify the metal fragments---it will help the detctive identify the locations traveled by the person who did the ...
February 26, 2012 by Jimmy

chemistry
The question I am having trouble with is: Scientists originally were uncertain whether the oxygen gas produced during photosynthesis came from CO2, H2O, or from both. How could radioisotope tracers be used to settle that question? Chemistry - DrBob222 6CO2 + 6H2O ==> ...
April 15, 2013 by Madison

Chemistry
A closed container is filled with oxygen. The pressure in the container is 435kPa . What is the pressure in millimeters of mercury? (i know that 1atm=760mm Hg=101,325 Pa) How do I use this to solve for the question? so: 435kPa*101,325=44,076,375Pa, & O2 = 32g/mol & you must ...
October 20, 2007 by leo

Chemistry
6 separate questions. I have figured out the other 20 questions I am stuck. Please help Thanks The correct name for the ionic compound Al2Se3 is? The correct name for the ionic compound Fe2Se3 is? the Roman numerall III in the name Iron(III)oxice indicates what? Which of the ...
February 9, 2014 by Lisa

Science
1. Which of the following types of waste should not be recycled at home? a. expired medicines b. glass bottles c. papers d. plastic bags 2. Which of the following is NOT a method of disposing hazardous wastes? a. burying them in deep rock layers b. incinerating them c. putting...
May 19, 2014 by Calvin

Chemistry
Acid Question!? An unusual category of acids known as superacids, which are defined as any acid stronger than 100% sulfuric acid, can be prepared by seemingly simple reactions similar to the one below. In this example, the reaction of anhydrous HF with SbF5 produces the ...
March 30, 2007 by Anonymous

Physics to Elena
Estimate the total binding energy for copper. 550 MeV Estimate the energy, in joules, needed to break a 3.0g copper penny into its constituent nucleons. E= in Joules Please help me out I got 1st part I need the Energy in joules am confused please help me out...thanks Physics...
May 8, 2013 by Leila

Chem - oxides
When an element is burnt in excess oxygen, is the oxide formed always: 1. a crystalline solid 2. greater in mass than the element 3. soluble in water 4. white in color alright, i know that most oxides are not soluble in water other than group 1 elements and calcium and barium...
September 23, 2009 by Monica

chemistry
I did an experiment where i put iron nail with zinc metal wrapped around it in agar solution. the solution turned pink. I have to find the anode: anode reaction: cathode (remember, a metal can be an inactive electrode): cathode reaction (there aren’t any metal ions present, so...
March 10, 2009 by Anonymous

chemistry
hi, Can you please double check to see if i have got this right? Is the empirical formual for oxide of arsenic As2O5? Cheers ;) Arsenic forms two oxides with oxygen. One is As2O5, the other is As2O3. I'm glad you posted today; please tell your friend you were talking with ...
February 7, 2007 by bertie

SCIENCE
WHY CAN'T HUMANS LIVE ON VENUS? Too hot, no oxygen and very high atmospheric pressure. But this doesn't mean that we could live there, it only means that we can't walk on the surface without protection. Thank you for using the Jiskha Homework Help Forum. Well, life on Venus "...
June 4, 2007 by I NEED HELP QUICKLY!!! PLEASE HELP ME

chemistry
Which of the following statements concerning differences between ionic and molecular compounds is correct? Molecular compounds contains two elements, and ionic compounds contain three of more elements ionic compounds contain oxygen, and molecular compounds do not. molecular ...
February 23, 2014 by Johnny

Biology
37. Wings, fins, and arms are limb adaptations that allow mammals to a. live in different environments b. attain diverse sizes c. nurse their young d. communicate with other mammals A? 4. Which is NOT a characteristic of function of the epidermis? a. repair of damaged cells b...
March 18, 2010 by mysterychicken

Biology
37. Wings, fins, and arms are limb adaptations that allow mammals to a. live in different environments b. attain diverse sizes c. nurse their young d. communicate with other mammals A? 4. Which is NOT a characteristic of function of the epidermis? a. repair of damaged cells b...
March 18, 2010 by mysterychicken

physics
If a gasoline engine has an efficiency of 21 percent and loses 780 J to the cooling system and exhaust during each cycle, how much work is done by the engine? Is it 3709.5??? Chemical energy in (as fuel and oxygen) = Work out + Heat out 21% is the ratio of Work out to Chemical...
February 15, 2007 by anonymous

Chemistry: Please check answers
1. Which of the following compounds is an unsaturated hydrocarbon? methane *propyne nonane methyl 2. The general name for hydrocarbons with at least one triple covalent bond is ____. alkenes alkyls alkanes *alkynes 3. What is the name of the smallest alkyne? butyne *ethyne ...
April 11, 2013 by Cassie

Chemistry
Which of the following reactions is exothermic? 1. Na(s) --> Na(g) 2. Na(g) --> Na+ + e- 3. Cl2(g) --> 2Cl(g) 4. Cl(g) + e- --> Cl-1 My guess is 4, but I'm not sure Here is what you do. For 1, do we think it will take energy to change Na as a solid to Na as a gas. ...
April 30, 2007 by Fiona

chemistry
1 _____is defined as one-half of the distance between the nuclei of two adjacent metal atoms in the close packed crystal lattice ionic radius metallic radius covalent radius atomic radius 2 Except for rubidium and caesium, all common cations are smaller than all common anions ...
April 23, 2012 by mike

Chemistry
1. A cylinder of Xenon has a volume of 750. ml. At 25.0°C the cylinder has a pressure of 655 torr. How much Argon is present in the cylinder? a. 240. moles b. 0.0264 moles c. .315 moles d. 26.5 moles 2.If a 25 liter cylinder of gaseous ammonia at atmospheric pressure (1.0 atm...
March 4, 2011 by E

Stiochiometry
Equation 2Mg+O2= 2MgO Lab data: Magnesium ribbon= .04 grams Magnesium Oxide= .09 2. Using the initial mass of magnesium, calculate the moles of oxygen and then moles of magnesium oxide produced. What is the mole ratio of the reactants? 3. Calculate the mass of magnesium oxide ...
February 26, 2009 by Emily

Solar Energy - Engineering
In the process of electrolysis, electrical power is used to separate water into oxygen and hydrogen molecules via the reaction: H2O --> H2 + ½O2 This is very much like running a hydrogen fuel cell in reverse. We assume that only the activation potential for the hydrogen ...
December 18, 2013 by Chris

chem
Show work 1. How many moles of oxygen will occupy a volume of 2.50 liters at 121.6 kPa and 331 K? 2. An unknown volume of chlorine gas (Cl2) is resting at 127 °C at a of pressure 152.4 kPa. If the gas weighs 191.4 g, what is the volume? 3. A 2.917 mole sample of an ideal gas ...
February 22, 2015 by theresa

Chemistry
Im studying for the MCAT and i found this question in my old chem book. i can't figure out how to derive the formula they are talking about... Nitrogen monoxide reacts with oxygen to give nitrogen dioxide. 2 NO(g)+ O2(g) --> 2 NO2(g) The rate law is -[NO]/t...
August 4, 2014 by Jesse

Chemistry
Im studying for the MCAT and i found this question in my old chem book. i can't figure out how to derive the formula they are talking about... Nitrogen monoxide reacts with oxygen to give nitrogen dioxide. 2 NO(g)+ O2(g) --> 2 NO2(g) The rate law is -[NO]/t...
August 4, 2014 by Jesse

Ion charge & formulas of ionic compunds-DrBob222
These are the other questions: I'll start from Number 1. 1. I have to write down the symbol for the following ions: a- sodium = Na b- chloride = CL c- sulfate = S d- ammonium = ? would it be NH4? e- chromium (II) = Cr f- chromium(III) = Cr 2. write the formulas for the ...
April 20, 2010 by Sara

Chemistry
ASpirin, c9h8o4, is prepared by reating salicylic acid, c7h6o3, with acetic anhydride, c4h6o3, in the reaction. c7h6o3 + c4h6o3---> c9h8o4 + c2h4o2 A student is told to prepare 45.0 g of aspirin. she is also told to use a 55.0 % excess of acetic anhydride and to expect to ...
September 22, 2008 by Komal

ELA
  Which of the following is a way you could begin an essay that's about the medical uses of iodine?      A. Last summer, a splinter in my brother's leg became infected, which led to blood poisoning. He could have prevented the problem with a few drops of iodine. B. The Winter ...
May 5, 2015 by Brooklyn

ELA
Which of the following is a way you could begin an essay that's about the medical uses of iodine?       A. Last summer, a splinter in my brother's leg became infected, which led to blood poisoning. He could have prevented the problem with a few drops of iodine.  B. The Winter ...
May 6, 2015 by Brooklyn

Biology
Under which condition can you hold your breath longer? First breathe in as much as you can and hold your breath, and time it. (Lungs completely inflated) After, breathe out as much as you can, hold your breath, and time it. (Maximal expiration). Which condition can you hold ...
February 15, 2010 by so CONFUSED!

Chemistry
Water is added to 4.267 grams of UF6. The only products are 3.730 grams of a solid containing only uranium, oxygen and fluorine and 0.970 gram of gas. The gas is 95.0% flourine, and the remainder is hydrogen. From data determine the empirical formula of the gas. What fraction ...
January 9, 2011 by deanna

chemistry
Water is added to 4.267 grams of UF6. The only products are 3.730 grams of a solid containing only uranium, oxygen and fluorine and 0.970 gram of gas. The gas is 95.0% flourine, and the remainder is hydrogen. From data determine the empirical formula of the gas. What fraction...
January 9, 2011 by Deanne

stiochiometry
Hello! This is my take home final for my chemistry class and I can use any resources to help me solve the questions. Can someone help me get started on all of them? Thanks… (note: he wants us to solve them using stoichiometry) 1. The resting calorie use of a human is about 1,...
May 16, 2008 by Roberta

Environmental Science
What is a process within the cell of an organism that uses glucose and oxygen to produce carbon dioxide, water, and energy called? It could be called oxidation (by a chemist), or metabolism (by a biologist). The body metabolizes glucose in various ways. See http://www.carbs-...
December 22, 2006 by Qiayamah

Biology
19. Which is NOT a general characteristic of plants? a. use oxygen to make usable energy b. primary producers c. have specialized cells d. cell walls composed of cellulose I think it might be either A or B... 24. During initial HIV infection, the HIV virus attaches to CD4 ...
February 20, 2010 by mysterychicken

Chemistry
When we breathe we inhale oxygen, O2, and exhale carbon dioxide, CO2, plus water vapor, H2O. Which likely has more mass, the air that we inhale or the same volume of air we exhale? Does breathing cause you to lose or gain weight? I thought that the air we breathe out has more ...
October 30, 2009 by Mary

Chem
Im studying for the MCAT and i found this question in my old chem book. i can't figure out how to derive the formula they are talking about... Nitrogen monoxide reacts with oxygen to give nitrogen dioxide. 2 NO(g)+ O2(g) --> 2 NO2(g) The rate law is -[NO]/t...
August 4, 2014 by Jesse

Chem
Im studying for the MCAT and i found this question in my old chem book. i can't figure out how to derive the formula they are talking about... Nitrogen monoxide reacts with oxygen to give nitrogen dioxide. 2 NO(g)+ O2(g) --> 2 NO2(g) The rate law is -[NO]/t...
August 4, 2014 by Jesse

Biology--Urgent
Need help with this: 'Social bees survive by collecting nectar or pollen from flowers, pollinating the flower in the process. They must keep their hives at a constant temperature, moisture, and oxygen content for their larvae to develop. One way they do this is by beating ...
January 26, 2010 by mysterychicken

Chemistry balancing equations
Translate each of the following reactions into complete balanced chemical equations using international symbols & include states of matter at SATP. Assume pure states of matter unless otherwise indicated. I really need help with this stuff please. 1. The reaction of magnesium ...
December 2, 2011 by Fizzylicous

Chemistry
A 500g iron (Fe) rod was left in air for a long period of time, and got covered with rust (Fe2O3) as a result of reaction with atmospheric oxygen. The mass of the rusty rod was determined as 560g. a) calculate the theoretical yield of Fe2O3(s), that is the mass of Fe2O3(s) ...
March 18, 2012 by Riley

biology
1. The energy used by living organisms a. is declining through time. b. is derived by breaking bonds that hold the atoms in organic molecules together. c. involves ionic bonds more often than covalent bonds. d. is available only from glucose when it undergoes respiration. e. ...
June 24, 2011 by akim

Science
What are the disadvantages of cutting down rainforests? I've already looked it up and got some info, so if anyone knows any additional info i could add to it, I'd appreciate it. Well, here's what I got: -Trees produce Oxygen and carbon dioxide -farmers CAN use the land, but it...
January 12, 2009 by John

Chemisry
Write a balanced equation using the correct formulas and include conditions (s,l,g or aq) for each of the following reactions. 1)Carbon monoxide gas reacts oxygen gas to produce carbon dioxide gas. Express your answer as a chemical equation. Identify all of the phases in your ...
November 14, 2010 by TMV

I NEED HELLLLPPPPP!!!!
Ive been looking all over and i cant find out if there is such thing as a carbon dioxide deficiency in hemoglobin (red blood cells)...i know theres an oxygen one called anemia but i really need one for carbon dioxide as a waste from the body....plz plz plz plz help me!! See ...
April 22, 2007 by said so

Science
Natural rubidium has an average mass of 85.4678 amu and is composed of isotopes 85Rb (mass = 84.9117 amu) and 87Rb. The ratio of the isotopes 85Rb/87Rb in natural rubidium is 2.591. What is the mass of 87Rb? Let x be the fraction of the Rb atoms that are Rb85. x/2.591 is the ...
January 13, 2007 by Gil

Chemistry
Identify 2 examples of the atoms or groups in the compound tocainide that could be involved in its binding to receptor sites in the body via hydrogen bonding. Give reasons for your conclusions. I have gathered that OH- and NH- bonds are an option, is this correct and if so why...
March 14, 2007 by Bean

calculus
Carbon-14 is a radioactive substance produced in the Earth's atmosphere and then absorbed by plants and animals on the surface of the earth. It has a half-life (the time it takes for half the amount of a sample to decay) of approximately 5730 years. Using this known piece of ...
July 24, 2009 by j

Chemistry
Ok, so in my gen chem 1 class, the teacher showed us that ethanol would not dissolve a sugar cube while water dissolves a sugar cube easily. No explanation was given, she just told us we would find out in gen chem 2. Here i am in gen chem 2, and the same thing is shown to us ...
August 31, 2011 by Kevin

physics
When two bodies are charged, the total charge before and after charging remains the same because of: A. quantization of charges B. conservation of charges C. law of induction D. Coulomb's law it is B? When a conducting sphere is charged positively, intially the charge is ...
April 7, 2009 by sophie

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