CHEM_ reflection paper 6

The compound diborane (B2H6) was at one time considered for use as a rocket fuel. Its combustion reaction is B2H6(g) + 3 O2(l) → 2 HBO2(g) + 2 H2O(l) The fact that HBO2, a reactive compound, was produced rather than the relatively inert B2O3 was a factor in the discontinuation of the investigation of the diborane as a fuel. What mass of liquid oxygen (LOX) would be needed to burn 234.4 g of B2H6? Answer in units of g.

MN IN The 1995 Nobel Prize in Chemistry was shared by Paul Crutzen, F. Sherwood Rowland, and Mario Molina for their work concerning the formation and decomposition of ozone in the stratosphere. Rowland and Molina hypothesized that chlorofluorocarbons (CFCS) in the stratosphere break down upon exposure to UV radiation, producing chlorine atoms. Chlorine was previously identified as a catalyst in the breakdown of ozone into oxygen gas. Using the enthalpy of reaction for two reactions with ozone, determine the enthalpy of reaction for the reaction of chlorine with ozone. (1) CIO(g) + O,(g) → Cl(g) + 20,(g) AHxn = -122.8 kJ AHn = -285.3 kJ | rxn AHn = ? (3)°O + (3)OIƆ (3)1Ɔ+(3)*o (£) (3) 0E – (3)°07 (2) rxn %3D = UXHV kJ MacBook Pro Q Search or enter website name The & %23 $4 3. 4. 5. 7. 6. delete R H. K. re B. HE MOSISO command option

Is the formation of atmospheric nitric acid more likely to occur during the day or the night? Explain your answer.

Explosions cause damage through the by-products of exothermic chemical reactions. Which is not one of those by-products? Question 15Answer   a.   Deflagration b.   Blast wave c.   Fireball d.   Hot gases

Reaction 1 FeO(s) + CO(g) → Fe(1) + CO2(g) AG" > 0 Reaction 2: C(s) + CO2(g) → 2 CO(g) AGzn <0 Overall reaction: FeO(s) + C(s) → Fe(l) + CO(g) AG n < 0 Subm The chemical equations above represent the main reactions that occur during the production of Fe(l) under certain conditions. The overall reaction couples reactions 1 and 2, resulting in a < 0? thermodynamically favorable process. Which of the following best explains whether or not a particle diagram could represent how the coupling of reaction 1 and reaction 2 results in AG A particle diagram that represents the increase in the volume of gaseous product particles would be a good representation of how the coupling of reactions 1 and 2 results in a thermodynamically favorable process. A particle diagram that represents the decrease in the average kinetic energy of the particles would be a good representation of how the coupling of reactions 1 and 2 results in a thermodynamically favorable process. A particle diagram cannot represent…

i)16O and 18O are two different isotopes of oxygen. What is  ONE IS TRUE about 18O? it less easily evaporated than 16O it is more volatile and reactive than 16O it is lighter than 16O it is more commonly occurring than 16O II) Ice core samples taken from Antarctica have been used to estimate changes in surface temperatures and the atmospheric concentrations of carbon dioxide and methane. This data indicates that when the temperature is relatively warm, the amounts of carbon dioxide and methane are ___________ Select one: relatively low (negative correlation) sometimes high, sometimes low (no correlation) relatively high (positive correlation) III) The answer to the previous above question indicates that ___________ . Select one: high atmospheric concentrations of carbon dioxide and methane might lead to warmer temperatures high atmospheric concentrations of carbon dioxide and methane might lead to cooler temperatures there is no…

When ozone levels in urban area reach unhealthy levels, residents are typically urged to avoid refuelingtheir cars during daylight hours. Explain how this might help to reduce smog formation?

Chapter #3, Question #13: Consider the following data for total atmospheric column ozone measurements (as DU) at three locations around the Earth, obtained using the TOMS in 2001.   January 15 april 15 july 15 october 15 Tierra del fuego (Chilie, argentina) 323 261 339 206 Nairobi (Kenya) 234 273 266 (Aug. 15) 266 Kiev (Ukraine) 321 420 314 273   Assume that these are typical of values that might be obtained in any other year, and discuss the trends as you move down the columns and along the rows, in terms of your knowledge of stratospheric ozone behavior.