It is often said that water vapour amplifies the Earth’s greenhouse effect. Indicate one way that an increased atmospheric concentration water vapour can increase the greenhouse effect and one way that it can decrease the greenhouse effect.

What is mutualism? Give an example of mutualism. Explain your answer

THERMOCHEMISTRY 237 23 3. A student wishes to determine the enthalpy of the reaction of hydrogen gas with chlorine gas by the reaction represented below. A high-pressure bomb calorimeter is used for this experiment. A 500.-mL high-pressure cell is filled with an equimolar mixture of H,(g) and CL,(g) to a total pressure of 10.00 atm and 293.50 K. H,(g) + CL(g) → 2 HCI(g) (a) If the reaction goes to completion, how many moles of HClI(g) can be produced? (b) The high-pressure sealed cell was placed in the bomb calorimeter and the mixture was ignited with an internal spark. The temperature of the calorimeter rose from 293.50 K to 298.83 K. If the previously-measured heat capacity of the whole calorimeter was C 3.60 kJ/K, calculate the heat transferred to the calorimeter by the reaction. (c) Calculate the experimental enthalpy of reaction in kJ/moln

A student dissolves 10.8 g of ammonium nitrate (NH4NO₂) in 250. g of water in a well-insulated open cup. He then observes the temperature of the water fall from 20.0 °C to 16.1 °C over the course of 8.4 minutes. Use this data, and any information you need from the ALEKS Data resource, to answer the questions below about this reaction: NH4NO3(s) NH(aq) + NO3(aq) You can make any reasonable assumptions about the physical properties of the solution. Be sure answers you calculate using measured data are rounded to 2 significant digits. Note for advanced students: it's possible the student did not do the experiment carefully, and the values you calculate may not be the same as the known and published values for this reaction. Is this reaction exothermic, endothermic, or neither? If you said the reaction was exothermic or endothermic, calculate the amount of heat that was released or absorbed by the reaction in this case. Calculate the reaction enthalpy ΔΗ per mole of NH4NO3. rxn exothermic…

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The enthalpy change for a chemical reaction is the sum of the energy consumed in breaking bonds and the energy released during bond formation. One way to determine the overall energy change for a chemical reaction is to apply Hess’s law to add together a group of reactions which can be arranged such that the chemical equations, when combined, give the overall equation we are trying to characterize.     a. Write a balanced chemical equation for the combustion of gaseous propane in gaseous oxygen to produce gaseous carbon dioxide and liquid water.      C3​H8​(g)+    O2​(g) ---->CO2​(g)+     H2​O(g)   b. Combine the following equations to determine the enthalpy change for the combustion of 1 mole of propane. Assume that solid carbon is graphite.  3C(s,graphite)+4H2​(g)--->C3​H8​(g) ΔHo = -103.8 kJ/mol   C(s,graphite)+O2​(g)--->CO2​(g) ΔHo= -393.5 kJ/mol   H2​(g)+1/2​ O2​(g)--->H2​O(g) ΔHo= -285.8 kJ/mol      kJ/mol…