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February 19, 2017

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

Number of results: 6,907

SCIENCE
CAN SOMEONE PLEASE HELP ME AND TELL ME IF IM RIGHT OR WHAT ????!!!!!!!!! Explain which statement is correct: energy is lost when water is boiled or the energy used to boil water is present, but it is no longer in a usable form unless you use work or heat to make it usable. i ...
April 28, 2009 by bobbi

science
CAN SOMEONE PLEASE HELP ME AND TELL ME IF IM RIGHT Explain which statement is correct: energy is lost when water is boiled or the energy used to boil water is present, but it is no longer in a usable form unless you use work or heat to make it usable. i think that the 2nd one ...
April 28, 2009 by bobbi

chemistry
An experiment is set up in which a copper surface is irradiated with high-intensity photons with a wavelength of 15.0nm. Electrons ejected from the surface are found to have a velocity of .548% of c. What is the binding energy of copper's most weakly bound electrons? What is ...
June 28, 2012 by Anonymous

science
how do i balance this equation: sodium hydroxide reacting with sulfurous acid [1 mol sulfurous acid reacts with 2 moles hydroxide ion] my hydrogens aren't balancing right 2 NaOH + H2SO3 -> Na2SO3 + 2 H2O ah thx, i accidently wrote H3O Why are oxygen tanks and spacesuits ...
October 19, 2006 by Dan

chemistry PLEASE HELPPPP
10.0 grams of carbon dioxide and 20.0 grams of oxygen are mixed in a 50.0 L container at 30.0 degrees celcius. What is the pressure of this mixture in mm Hg? I defined my variables. so i had Mass=30.0g Volume=50.0L Temperature=303 Kelvin pressure=x. then i used PV*GFM=mRT. (x...
March 18, 2008 by Miley

Chemistry
8.40 grams of Hydrogen gas reacts with 48.2 grams of Oxygen gas. Give the mass of the water vapor produced and the mass of the excess reactant left over. Can somebody please explain stoichiometry to me? I've failed the test and the retest. I'm usually able to balance the ...
November 29, 2010 by Anna

anatomy
If the pleural space lost its negative pressure which of the following would be true? A.Inspiation would be more difficult B.Expiration would be more difficult C.Sufactant wouldnt be needed D. Exchange of oxygen and carbon dioxide would improve I think it is would be D but not...
September 27, 2008 by uknown

biology
Explain how respiration and the circulatory system work together when an individual is exercising. Does tissue need oxygen at a higher rate? Does tissue need to void CO2 at a higher rate? Does the heart pulse speed up? Does the breathing rate increase?
June 7, 2007 by Gabrielle

Science help,Anyone?
1. Why is it rare for the soft parts of an organism to become a fossil? The soft parts take a long time to decay. The soft parts can be eaten by other animals. The soft parts cannot be buried in sediment. The soft parts form petrified fossils. 2. Which of the following terms ...
December 10, 2013 by Princess Anna

Chemistry
A sample of oxygen is collected in a 387 mL container over water at 15◦C, and the barom- eter reads 738 torr. What volume would the dry gas occupy at 781 torr and 15◦C? Water’s partial pressure at 15◦C is 12.8 torr. Answer in units of mL
November 20, 2012 by Caitlin

solid chemestry
A p-n junction is obtained at a depth of 3 x 10-3 cm below the surface by diffusion of antimony (Sb) into p-type germanium. What is the donor concentration in the bulk germanium if the diffusion is carried out for three hours at 790 C? Express your answer in number of donor ...
November 15, 2013 by Anonymous

To: Bobpursely
You helped me with my observations yesterday, but I need help with my questions as well. I tried to answer as many as I could by myself, but I'm having difficulties understanding some. Pointing me towards the right direction would be helpful, thanks. Questions: Which changes ...
April 7, 2010 by Sara

chem help
a scuba diver breathing normal air descends 100m of depth, where the total pressure is 11 atm. What is the partial pressure of oxygen that the diver experiences at this depth? Can someone help out on this question? Make a ratio: 11atm/1atm= P/partial pressureO2 at surface ...
March 19, 2007 by david

chemistry
In the formation of smog, nitrogen and oxygen gas react to form nitrogen dioxide: N2(g)+2O2(g)→2NO2(g)How many grams of NO2 will be produced when 2.1L of nitrogen at 840mmHg and 28∘C are completely reacted? I know that you use the equation n=PV/RT to get the number...
October 26, 2013 by ellie

Science
the active ingredient in the alergy medication claritin contain carbon,hydrogen,chloride,nitrogen,and oxygen its molecules formula is C22H23ClN2O2.the standard adult gosage utizies 1.572*10^19 molecules of the spicies determine the mass gosage of the active ingridient in the ...
February 2, 2016 by Kriatian ferrer

Chemistry
A compound of Tin Sulfate is decomposed in the lab to give 1.91g of Tin, 1.03 grams of Sulfur, and 2.06g Oxygen. Determine if this is a compound of Tin(II) Sulfate or Tin(IV) Sulfate.
February 16, 2013 by Dylan

AP Chemistry
Textrodotoxin is a toxic chemical found in fugu pufferish, a popular but rare delicacy in Japan. The compound has a LD50 (the amount of substance that is lethal to 50% of a population of iron (iii) hydroxide. Textrodotoxin is 41.38% carbon by mass, 13.16% nitrogen by mass, and...
October 15, 2009 by Rose23

chemistry
A 0.016076-mol sample of an organic compound was burned in oxygen in a bomb calorimeter. The temperature of the calorimeter increased from 23.7oC to 24.5oC. If the heat capacity of the calorimeter is 4.98 kJ (oC)-1, then what is the constant volume heat of combustion of this ...
March 1, 2014 by abby

chemistry
A 0.016076-mol sample of an organic compound was burned in oxygen in a bomb calorimeter. The temperature of the calorimeter increased from 23.7oC to 24.5oC. If the heat capacity of the calorimeter is 4.98 kJ (oC)-1, then what is the constant volume heat of combustion of this ...
March 5, 2014 by abby

Chemistry
Choose an alkane that is 6 to 10 carbon atoms in length. List the alkane's name and the other isomers you can properly draw and name. For example: Decane / isomer 2 methyl-Nonane. Do not guess. Draw out on paper then name for best results. Include the drawing of the alkane and...
May 27, 2016 by Anonymous

Flotation is widely used for processing all kinds
In most instances, flotation is used for processing sulfide auriferous ores whose flotability is quite high and the effect is most notable. By flotation, the gold can be enriched to sulfide ore concentrate as much as possible and the abandoned tailings can be got. The ore ...
July 22, 2012 by jiandan

Chemistry
Can you please someone check my answer for me? I don't know how to start thses answer. Chemistry is not my things. Please give me answers. :( a)Determine the number of grams in 0.750 moles of the compound Iron(II)phosphate: Fe3(PO4)2. Answer: ? b)How many atoms of iron are in ...
March 31, 2010 by Anonymous

Jefferson
Nitric acid and zinc react to form zinc nitrate, ammonium nitrate, and water. 4Zn(s) + 10HNO3(aq)→ 4Zn(NO3)2(aq) + NH4NO3(aq) + 3H2O(l) A. How many atoms of zinc react with 1.49g HNO3? B. Calculate the number of grams of zinc that must react with an excess of HNO3 to ...
January 7, 2013 by Gloria

chemistry
Nitric acid and zinc react to form zinc nitrate, ammonium nitrate, and water. 4Zn(s) + 10HNO3(aq) → 4Zn(NO3)2(aq) + NH4NO3(aq) + 3H2O(l) A. How many atoms of zinc react with 1.49g HNO3? B. Calculate the number of grams of zinc that must react with an excess of HNO3 to ...
January 7, 2013 by Anonymous

Physics
The masses of 1 mole of various gases are as follows: hydrogen about 2 grams, helium about 4 grams, nitrogen about 28 grams, oxygen about 32 grams and carbon dioxide about 44 grams. On the average how fast does a molecule of each gas move at 333 Celsius?
April 6, 2010 by Benny

physics
The masses of 1 mole of various gases are as follows: hydrogen about 2 grams, helium about 4 grams, nitrogen about 28 grams, oxygen about 32 grams and carbon dioxide about 44 grams. On the average how fast does a molecule of each gas move at 333 Celsius?
April 6, 2010 by Plaster

Chemistry
which of the following statements are true? a) For an acid H-O-A : the greater the electronegativity of A, the weaker the acid HA b) For an acid H-A : the weaker the H-A bond, the stronger the acid H-A c) HF is a stronger acid than HCl d) HClO4 is a weaker acid than HClO2 e) ...
October 15, 2009 by Anonymous

Science: Chemistry
1. The element gold, Au, has a face-centered cubic structure. (Density - 19.3 g/cm^3) (a) What are the # of gold atoms in 1 unit cell? (b) What are the # of unit cells in 1 mol? (c) What is the volume of 1 mol gold unit cells? (d) What is the volume of 1 unit cell? (e) what is...
November 8, 2014 by Supriya

Gases - van der waals
It turns out that the van der Waals constant b equals four times the total volume actually occupied by the molecules of a mole of gas. Using this figure, calculate the fraction of volume in a container actually ocupied by Ar atoms (a) at STP, (b) at 100 atm pressure and 0 ...
December 7, 2006 by Jenn

Math/Chemistry
the atomic mass of an element is the mass, in grams, of one mole (mol), or 6.02 * 10^23. A.) How many atoms are there in 3.5 mol od carbon? B.) If you know that 3.5 mol of carbon weighs 42 grams, what is the atomic mass? C.)Using you answer from (B), find the approximate mass ...
August 22, 2011 by Chaney

chemistry
Which of the following is a feature of an aromatic compound? Which of the following is a feature of an aromatic compound? It has a strong aroma. Its formula contains only six carbon atoms. It contains a benzene ring. It contains only carbon-carbon double bonds.
November 7, 2014 by Shatoya

science
when can the plant start to make its own food? A plant always makes its own food. Ever since it existed it made its own food through photosynthesis. The leaves take in the sunlight and form it into food. It also releases oxygen.
February 27, 2007 by christina

chemistry
Consider the following reaction: 2 NO(g) + O2(g) ---> 2 NO2(g) + energy if the number of moles of oxygen is increased to two moles, the a. reaction speeds up b. reaction slows down c. temperature increases d. temperature decreases I'm not really sure what the answer to this...
February 21, 2012 by Aria

Chemistry-Explanation Please
Oxygen gas can be generated by heating KClO3 in the presence of some MnO2. 2KClO3 → 2KCl + 3O2 If all the KClO3 in a mixture containing 1.00 g KClO3 and 0.25 g MnO2 is decomposed, how many liters of O2 gas will be generated at T = 24.0°C and P = 755.6 torr?
November 1, 2012 by Kwame

chemistry
When a 6.79-g mixture of methane, CH4, and ethane, C2H6, is burned in oxygen at constant pressure, 369 kJ of heat is liberated. What is the percentage by mass of CH4 in the mixture? The standard enthalpies of combustion for CH4 and C2H6 are -890.3 kJ mol-1 and -1569.7 kJ mol-1...
March 1, 2014 by abby

Chemistry+need help checking work
Using aervage atmoic masses for each of the following elements, calculate the mass, in amu (grams) A. 635 atoms of hydrogen ---> 1 mole of H = 1.01g = 6.022 x 10^23 atom 635 atom of H 1.01g/6.022 x 10^23 atom I got 1.06 x 10^-21 amu. I got that answer buying the "E" button ...
January 7, 2009 by Chopsticks

HS Science
I have 4 questions 1 What is the equation for the acid ionization constant of HI? 2 Give the oxidation numbers of all atoms in NaMnO4 3 An atom changes its oxidation number from -2 to -5. Is it oxidized or reduced? How many electrons did it take to do this? 4 An atom changes ...
June 30, 2011 by Ashley

Chemistry
1. The eleent gold, Au, has a face-centered cubic structure. (Density - 19.3 g/cm^3) (a) What are the # of gold atoms in 1 unit cell? (b) What are the # of unit cells in 1 mol? (c) What is the volume of 1 mol gold unit cells? (d) What is the volume of 1 unit cell? (e) what is ...
November 8, 2014 by Supriya

Chemistry
Hi Im reposting incase my original post doesn't get read. Please see bottom for additional info that I need help getting verified. Many thanks Hi Please help verify my answer to the following question: 0.500g of pure phosphorous was burned in excess pure oxygen to give a ...
October 16, 2011 by Helpme

chemistry
A sample contains Hydrogen atom ,He+ ion, Li2+, & Be3+ ion. In H atom electron is present in 8th orbit, in He2+ e- is present in 6th orbit, Li2+ in 5th orbit& in Be3+ electron is present in 4th orbit. All the atoms are de-excited to the ground state. Calculate the total no. of...
June 4, 2014 by Swapnil

Chemistry
A sample of iron weighing 15.0 g was heated with potassium chlorate (KClO3) in an evacuated container. The oxygen generated from the decomposition of KClO3 converted some of the Fe to Fe2O3. If the combined mass of Fe and Fe2O3 was 17.9g,calculate the mass of Fe2O3 formed and ...
August 22, 2013 by Francis

science
1.5173 g of organic iron compound containing FE , C ,H and O is burnt in oxygen gas produced 2.838 g OF carbon dioxide and 0.8122 g of water. In separate experiment to determine the mass % of iron, 0.3355 g of the compound yielded 0.0758 g iron (II) oxide. Determine the ...
June 28, 2016 by Nor

chemestry
At 298.K and 1.00 atm, assume that 22 mL of NO gas reacts with 18 mL of oxygen gas and excess water to produce nitric acid according to the following equation: O (g) H O(l) 2 HNO (g) 2 3 2NO(g) + 2 + 2 ¾¾® 3 . If all of the nitric acid produced by this reaction is collected...
November 2, 2010 by lore

chemistry
If 1.70 liters of 0.670 M CuSO4 solution is electrolyzed by passing 4.70 amps through the solution for 3.00 hr using inert electrodes. (a) As electrolysis proceeds, how does the acidity of the solution change? (b) How many grams of Cu metal are formed at the cathode? (c) How ...
November 19, 2010 by Dana

science
bornite(Cu3FeS3)is copper ore used in the production of copper.when heated,the following reaction occurs.2CuFeS3(s)+7oxygen(g)=6Cu(s)+2FeO(s)+6SO2(g)..IF 3.88 metric tons of bornite is reacted with excess oxygen and the process has 75.6 percent yield of copper,what mass of ...
June 13, 2011 by mushibwe lameck c

Chemistry
A neutral molecule is identified as a tetrafluoride, XF4, where X is an unknown atom. If the molecule has a dipole moment of 0.63 D, can you give some possibilities for the identity of X? (Select all that apply.) sulfur nitrogen oxygen polonium phosphorus selenium tellurium ...
June 17, 2011 by Lance

chemistry
a typical alberta home heated with natural gas assume methane CH4 (g) consuems 2.00ML of natural gas during the month of December. What volume of oxygen at SATP is required to burn 2.00ML of methane measured at 0 degrees and 120 kPa? the answer is 2.62ML but i do not know how ...
March 23, 2012 by anita

chemistry
Use the molar mass of the following in order to calculate the number of moles from the given masses. Watch the significant figures a) 0.025 g of oxygen b)0.657 g og copper c) 0.7 g of chlorine I know how to calculate with finding the molar mass but not this way. thank you so ...
October 27, 2014 by MC

HelpMeLinda
Hello miss Linda I really appreciate you explaning the topic thankyou very much my question is Why does stone (concrete) strong under compression ? can you explain me this and Why is Steel strong under tension ? thank a mil Well, stone is not always stronger under compression...
June 7, 2007 by Jr. Smith Laren

Chem: primitive cubic packing
Answer the following for a primitive cubic unit cell. For the type of packing answer, use letters (starting with A, then B, then C) without spaces and separated by hypens (-) to indicate the layers of solid present. type of packing =? type of holes =? # atoms / 1 unit cell = 1...
February 13, 2009 by Anonymous

Biology
Wine is made by mixing yeast with grapes and allowing the yeast cells to undergo fermentation. Sparkling wine is a type of wine that contains high levels of dissolved carbon dioxide. What is the source of the carbon atoms in the carbon dioxide found in sparkling wine? ethanol ...
February 1, 2016 by Steve

Check my Science questions?
1. Why is it rare for the soft parts of an organism to become a fossil? The soft parts take a long time to decay. The soft parts can be eaten by other animals. The soft parts cannot be buried in sediment. The soft parts form petrified fossils. 2. Which of the following terms ...
December 11, 2013 by Princess Anna

chem
A 75.0 L stainless steel container was charged with 3.00 atm of hydrogen gas and 4.00 atm of oxygen gas. A spark ignited the mixture, producing water. What is the pressure in the tank at 25°C? in atm What is the pressure in the tank at 125°C? in atm
November 17, 2007 by mel

chemistry
From the following combustion: 1-butanol + oxygen = carbon dioxide + water. How many grams of carbon dioxide and water are produced when 130.6 grams of 1-butanol is completely burned? Please help me! I have not a clue! Thanks so much!
November 28, 2009 by Turtle Lover

Biology
20. When the blood enters the gill filaments in a fish, its carbon dioxide content is ________ and oxygen content is _____ a. low;high b. low;low c. high;high d. high;low D? I'm not sure about this question... Thanks -MC
March 18, 2010 by mysterychicken

chem
A 4.91 g sample of aluminum completely reacts with oxygen to form 6.85 g of aluminum oxide. Use this data to calculate the mass percent composition of aluminum in aluminum oxide. i got 61.2% first and it was wrong. then i got 53.0% and it was wrong
November 11, 2010 by hannah

Chemistry! I need help quick! Thank you very much!
2h2O2 + 2H2O ---> 2H2O + O2 If 50cmcube , 2.0 mole/dmcube of hydrogen peroxide is decomposed and volume of oxygen gas collected. How much hydrogen peroxide is decomposed?
June 19, 2011 by Click6

chem/phys
Calculate the number of H2O molecules in a human body of mass 66.5 kg. Assume that, on average, water makes up 62% of the mass of a human body. (Use 1.0 u for the atomic mass of hydrogen, and 16.0 u for the atomic mass of oxygen.) 1
April 25, 2012 by opp

Chemistry
Chemical analysis of a gas shows that it contains one carbon atom for every one hydrogen atom. The densiry ofthis gas is 1.161 g/l at STP. What is the minimus oxygen volume needed at STP for the complete combustion of .500 mol of this gas?
October 25, 2010 by Taylor

Chemistry
I'm a bit iffy on oxidation numbers... can someone please tell me if this is correct? Assign oxidation states to each element on both sides of the equation : KClO2--->KCl+O2 Reactants K = +1 Cl = +1 O = -2 Products K = +1 Cl = -1 O = 0 the element being reduced is Cl and ...
May 20, 2012 by Katherine

chem
A sample containing 6.40 g O2 gas has a volume of 15.0 L. Pressure and temperature remain constant. a. What is the new volume if 0.600 mole O2 gas is added? b. Oxygen is released until the volume is 12.0L. How many moles of O2 are removed? c. What is the volume after 7.50 g He...
November 1, 2012 by tracy

chemistry
A researcher studying the nutritional value of a new candy places a 3.10-gram sample of the candy inside a bomb calorimeter and combusts it in excess oxygen. The observed temperature increase is 2.34 °C. If the heat capacity of the calorimeter is 33.50 kJ·K–1, how many ...
November 11, 2012 by Shireen Shaikh

ap chem
an unknown gaseous hydrocarbon reacts with oxygen to form CO2 and H2O, DETERMINE HEAT OF FORMATION FOR THE HYDROCARBON. the density of the mixture of CO2 and H2O at 1 atm and 200 degree celsius is 0.751g /L and heat of reaction is equal to -2044.5 KJ /MOL hydrocarbon
October 11, 2014 by Rita

Chemistry
A researcher studying the nutritional value of a new candy places a 5.80-gram sample of the candy inside a bomb calorimeter and combusts it in excess oxygen. The observed temperature increase is 2.93 °C. If the heat capacity of the calorimeter is 38.50 kJ·K–1, how many ...
February 23, 2015 by meg

chemistry
A researcher studying the nutritional value of a new candy places a 4.10-gram sample of the candy inside a bomb calorimeter and combusts it in excess oxygen. The observed temperature increase is 2.47 °C. If the heat capacity of the calorimeter is 33.90 kJ·K–1, how many ...
October 28, 2016 by anon

Chemistry 11th
Solid ammonium nitrate breaks down into nitrogen, water vapor, and oxygen. If there was 300g of the solid and the reaction happened under STP find the total volume of the products. (translating words to eqns., balancing eqns., understanding what STP means) thanks! P.S. eqns.=...
June 1, 2010 by Reyna

chemistry
Silver tarnishes (turns to Ag2S) in the presence of oxygen and hydrogen sulfide according to the following equation: 4Ag(s) + 2H2S(g) + O2(g) ¨ 2Ag2S(s) + 2H2O(l) Usually, H2S is the limiting reactant. If a silver spoon is placed in a container that holds 56.7mL of H2S at 1...
July 24, 2012 by Big Trav

Biology
What does your body need oxygen for A. It is necessary to aerate the brain C. Cells need it to produce the energy they need to function D. Air flow aids in blood flow within the blood vessels E. It produces hemoglobin, needed to carry carbon dioxide My teacher said letter b ...
December 2, 2015 by Keon

Chemistry
Atmospheric pressure on the peak of Mount Everest can be as low as 0.20 atm. If the volume of an oxygen tank is 10.0 L, at what pressure must the tank be filled so that the gas inside would occupy a volume of 1.2x10^3L at this pressure? Tried using the P1V1 = P2V2 formula and ...
May 4, 2016 by Gale

HONORS CHEMISTRY
A synthesis of nitrogen dioxide from nitrogen and oxygen. There are 5.000 mol of N2 and 8.000 mol of O2 mixed in a 5.000-L flask. What is the equilibrium constant for the synthesis?
March 17, 2010 by helpless

Chemistry
a compound of nitrogen and oxygen is 30.46% by mass N and 69.54% by mass O. the molar mass if the compound was determined to be 92g/mol. What is the empirical formula of the compound? What is the molecular formula of the compound?
October 22, 2014 by Gina

chemistry
Solid sodium nitrate can be decomposed to solid sodium nitrite and oxygen gas. If the percentage yield for the reaction is 80.4%, calculate the grams of sodium nitrite that will result from the decomposition of 955grams of sodium nitrate. 2 NaNO3 ¨ 2 NaNO2 + O2
May 15, 2009 by lama

Chemistry
a tank contains a mixture of 3.0 mol of nitrogen gas, 2.0 mol of oxygen gas and 1.0 of carbon dioxide gas at 25 degrees celsius and a total pressure of 10.0 atm. Calculate the partial pressure in torr of each gas in the mixture?
July 10, 2011 by Elizabeth

Chemistry
Very confused! Converting between grams of a compound and grams of a constituent element Determine the mass of oxygen in a 5.8 g of NaHCO3 5.8 g NaCHO3 * 1 mol NaCHO3/ 84.01 NaCHO3 * 48.00 mol O / 1 mol NaCHO3 * 16.00 g O/ 1 mol = I got 53 but the answer is 3.3 g O Help what ...
September 23, 2011 by Monique

Chemistry
What partial pressure of oxygen above the water (in atmospheres at 0 C ) is needed to obtain this concentration? The solubility of O2 in water at 0 C and 1 atm partial pressure is . 2.21 x 10^-3 mol/L Concentration needed is 4mg/L Stuck and need help, anything is appreciated!
September 21, 2014 by Joe

science
which of the following is true about Earths atmosphere? a)the atmosphere contains 78 percent water vapor b)the atmosphere contains 21 percent oxygen c)the atmosphere allows radiation from the sun to pass through and warm Earths surface
November 2, 2015 by Jerry Jones

Chemistry
Some (or all) of the structures below are representations are of the same molecule. How many unique structures are shown (i.e., how many structures with different molecular formulae)? Image: img6(dot)imageshack(dot)us/content.php?page=done&l=img6/5716/80685628.jpg&via=mupload ...
July 2, 2009 by Toronto

Chemistry
a)What mass of water is produced from the complete combustion of 2.30×10−3 g of methane? b)What mass of oxygen is needed for the complete combustion of 2.30×10−3 g of methane? This is the unbalanced equation given: CH4+O2->CO2+H2O
September 21, 2010 by Cindy

physics
Calculate the number of H2O molecules in a human body of mass 50.6 kg. Assume that, on average, water makes up 62% of the mass of a human body. (Use 1.0 u for the atomic mass of hydrogen, and 16.0 u for the atomic mass of oxygen.)
April 12, 2013 by kira

Physics
Calculate the number of H2O molecules in a human body of mass 65.9 kg. Assume that, on average, water makes up 62% of the mass of a human body. (Use 1.0 u for the atomic mass of hydrogen, and 16.0 u for the atomic mass of oxygen.)
April 27, 2014 by Steve

Science
1. The combination of sulfur dioxide, nitrogen oxide, and atmospheric moisture creates A. drinking water. B. smog. C. pesticides. D. acid rain. D? 2. Another name for unicellular organisms that dominated Earth up to the Precambrian time is A. eukaryotes. B. cyanobacteria. C. ...
January 29, 2014 by Beatrice

chemistry
Using the half-reaction method, balance the redox reaction below. Show your work; partial credit will be given. I- + Br2 → IO3- + Br- Write the reduction and oxidation half-reactions. Balance them for atoms. Balance each of the half-reactions for charge. Multiply the ...
April 27, 2012 by Anonymous

Kelsie
name the element wsith the atomic number z= 15 and the atomic mass number 31. How many electrons does the neutral of this lement have? How many neutrons does the neutral atoms of this element have? I know the element with the atomic number of 15 and atomic mass of 31 is ...
November 8, 2010 by CHEMISTRY

Chemistry again
Chromium is ametal that is added to steel to improve its resitance to corrosion. Calculate both the number of miles in a sample of Cr containing 5.00 x 10^20 atms and the mass of the sample. Ok this is how I worked it. 1 mole of Cr = 51.996g = 6.022 x 10^23 atoms (whatever ...
January 6, 2009 by Chopsticks

Chemistry
Use the experimental molar mass to determine the molecular formula for compounds having the following analyses. A. 41.39% carbon, 3.47% hydrogen, 55.14% Oxygen; experimental molar mass 116.07 I got C4H4O4 as the molecular formula. Can someone check this for me?
January 25, 2009 by Chopsticks

CHEMISTRY
1.A scuba diver's tank contains 0.29 kg of O2 compressed into a volume of 2.3 L. a)Calculate the gas pressure inside the tank when the temperature is 9oC. b)calculate the volume of oxygen if the temperature is 26oC and the pressure is 0.095 atm. somebody..plz help me...tq
June 6, 2013 by irfan

Biology
What is considered the most critical function of erythrocytes? the transport of oxygen the transport of carbon dioxide buffering against changes in blood pH assisting in clot formation All of the answers are considered the most critical functions of erythrocytes.
March 29, 2016 by Anonymous

Chemistry
CH4 + 2O2 --> CO2 + 2H2O a. How many grams of methane are needed to produce 1.5 X 10^-2 grams of carbon dioxide? b. How many grams of oxygen are needed to react to form the 1.5 X 10^-2 grams moles of carbon dioxide?
November 10, 2016 by John

Chemistry
CH4 + 2O2 --> CO2 + 2H2O a. How many grams of methane are needed to produce 1.5 X 10^-2 grams of carbon dioxide? b. How many grams of oxygen are needed to react to form the 1.5 X 10^-2 grams moles of carbon dioxide?
November 10, 2016 by John

Chemistry
CH4 + 2O2 --> CO2 + 2H2O a. How many grams of methane are needed to produce 1.5 X 10^-2 grams of carbon dioxide? b. How many grams of oxygen are needed to react to form the 1.5 X 10^-2 grams moles of carbon dioxide?
November 10, 2016 by John

science/chemistry
HELP,HELP,HELP,HELP How can you tell that cobalt(II) iodide is binary ionic compound formed by a transition metal with more than ionic charge? Thanx in Advance form jeff Cobalt(II) chloride tells you it is binary (composed of two different atoms), cobalt and iodine; compare ...
January 5, 2007 by Jeff

Chemistry
You have a tank of helium with a volume of 10 liters that is currently under 40 atm of pressure. If you open the valve on the tank and release the helium into a room with a volume of 10,000 liters, how many atmospheres of pressure will the helium now be under? Second, what ...
December 18, 2014 by Ryan

Chemistry Balancing Equations
Can you please tell me if these are correct? 1. Sodium Hydrogen Sulfite reacts with hydrochloric acid to produce sulfur dioxide gas, water and sodium chloride NaHSO3 + HCl -----> SO2 + H2O + NaCl 2. Sodium nitrate reacts with hydrochloric acid to produce nitrogen monoxide ...
March 14, 2011 by Anonymous

Chemistry
Draw the condensed structural formula for ethylbenzene, 1,3 dichlorobenzene,1,2 and 4-trimethylbenzene ? Any help would be appreciated, thank you I also was wondering if anyone could let me know if I am going in the correct direction with this question> Acetylene gas reacts...
July 26, 2010 by Beth

Chemistry
The ionic compund sometimes called yellow uranium is used to produce colored glazes for ceramics. It is 7.252% sodium, 75.084% uranium, and 17.664% oxygen a. What is the empirical formula for this compound? b. This compound has a molecular mass of 1268.06 g/mol, what is the ...
November 3, 2014 by Maria

Inorganic Chemistry
A researcher studying the nutritional value of a new candy places a 4.70-gram sample of the candy inside a bomb calorimeter and combusts it in excess oxygen. The observed temperature increase is 2.98 °C. If the heat capacity of the calorimeter is 39.80 kJ·K–1, how many ...
March 11, 2016 by Michael

chemistry
Write Skeleton equations for these reactions. A) Heating Copper(II) sulfide in the Presence of diatomic oxygen produces pure copper and sulfur dioxide gas. B)When heated, baking soda (Sodium hydrogen carbonate) decomposes to form the products sodium carbonate, carbon dioxide, ...
February 28, 2010 by Jack

science
One reason carbon monoxide (CO) is toxic in that it bind to the blood protein hemoglobin more strongly than oxygen does. The hemoglobin – CO bond absorbs radiation of 1953 cm–1, which are in units of wavenumbers. Wavenumber is defined as the reciprocal of wavelength, in ...
April 1, 2010 by Johannie

science
One reason carbon monoxide (CO) is toxic in that it bind to the blood protein hemoglobin more strongly than oxygen does. The hemoglobin – CO bond absorbs radiation of 1953 cm–1, which are in units of wavenumbers. Wavenumber is defined as the reciprocal of wavelength, in ...
April 1, 2010 by Johannie

Chemistry
Assuming all volume measurements are made at the same temperature and pressure, how many liters of carbon dioxide gas can be produced when 12.8 liters of oxygen gas react with excess carbon monoxide? Show all of the work used to solve this problem. Unbalanced equation: CO(g...
March 29, 2011 by Bob

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