In: Chemistry
At a certain temperature, the equilibrium constant for the following chemical equation is 4.00.
At this temperature, calculate the molarity (M) of NO2(g) that must be added to a starting concentration of 2.73 M SO2(g) (with no products initially present) in order to have formed 1.30 M SO3(g) and 1.30 M NO(g) when equilibrium is reached.
SO2(g)+NO2(g)−⇀↽−SO3(g)+NO(g)
molarity =
In: Chemistry
Consider the reaction:
8H2S(g)+4O2(g)?8H2O(g)+S8(g)
?[H2S]/?t = -0.047M/s .
Find ?[O2]/?t
Express your answer to two significant figures and include the appropriate units
Find ?[H2O]/?t
Express your answer to two significant figures and include the appropriate units.
Find ?[S8]/?t
Express your answer to two significant figures and include the appropriate units.
Find the rate of the reaction.
Express your answer to two significant figures and include the appropriate units.
In: Chemistry
In: Chemistry
A certain liquid has a vapor pressure of 92.0 Torr at 23.0 ∘ C and 390.0 Torr at 45.0 ∘ C. Calculate the value of Δ H ∘ vap for this liquid.
Calculate the normal boiling point of this liquid.
In: Chemistry
In: Chemistry
if a 4.000gram sample potassium acid phthalate is equivalent to 48.37 ml of a sodium hydroxide solution, what is the concentration of the latter?
In: Chemistry
Consider each of the following reactions and decide whether the standard entropy change for the reaction will be large & positive; or small; or large & negative. 1. large&negative 2. large&positive 3.small
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a) H2(g) + Cl2(g) = 2 HCl(g) |
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b) 2 Na(l) + H2(g) = 2 NaH(s) |
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c) 2 H2O(l) = 2 H2(g) + O2(g) |
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d) C(s) + H2O(g) = CO(g) + H2(g) |
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e) Cu(s) + 2 H2SO4(aq) = CuSO4(aq) + 2 H2O(l) + SO2(g) |
f) BaSO4(s) + 2 H2O(g) = BaSO4.2H2O(s)
2. Identify the true statement(s) regarding the entropy of chemical substances.
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All pure substances have a positive entropy at room temperature. |
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The dissolution of an ionic salt in water usually leads to an increase in entropy of the system (salt + water). |
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So(one mole O3(g)) > So(one mole O2(g)) at 25oC. |
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The entropy of ice at 0oC is lower than that of water at 0oC. |
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When a metallic crystal is heated, its entropy increases due to increasing atomic vibrations. |
In: Chemistry
Calculate the number of moles of ammonia needed to dissolve 0.0010 mole of silver chloride in 4000 mL of solution at 25 degrees Celsius. Ksp for AgCl is 1.8 x 10-10 and the dissociation constant for [Ag(NH3)2]+ is 6.3 x 10-8
In: Chemistry
550.0 gallons of 15.0 M nitric acid were added to a lake. The initial pH of the lake was 5.70 and the final pH was 4.50 . If none of the acid was consumed in chemical reactions, determine the volume of the lake.
In: Chemistry
Chemical analysis of an unknown compound gives a molar mass of
334 g/mol and a percentage composition of 75.42% carbon, 6.63% hydrogen,
8.38% nitrogen, and the rest is oxygen. Calculate the empirical and molecular
formulas for the unknown compound.
2.) Write a balanced chemical equation for the complete combustion of
pentane (C5H12). If 100.00 g of pentane are combusted in excess O2, what mass
of CO2 would be released to the atmosphere?
In: Chemistry
Calculate the percent by mass of the element listed first in the formulas for each of the following compounds. , 1-octanol C8H18O, calcium phosphate Ca3(PO4)2, 3-phenylphenol C12H10O, aluminum acetate Al(C2H3O2)3,
In: Chemistry
A stream of air (21mole% O2, the rest N2) flowing at a rate of 30 kg/h is mixed with a stream of CO2. The CO2 enters the mixer at a rate of 23.6 m3/h at 200 oC and 1.5 bar. What is the mole % of CO2 in the product gas? a) Calculate the number of kg. moles of air flowing b) Calculate the number of kg. moles of CO2 c) Calculate the mole percent of CO2 in the mixture?
In: Chemistry
It is recommended that drinking water contain 1.6 ppm of fluoride. If the local reservoir has a diameter of 450.0 m and a depth of 10.0 m (V= Pi*r2 *h), how many grams of F should be added to the water in the reservoir to give the recommended concentration? If fluoride is provided by hydrogen hexafluorosilicate (H2SiF6), how many grams of H2SiF6 contain Fluoride?
In: Chemistry
Glycogen and Fatty Acids are used to store energy. Describe and contrast the physiological states that would result in breakdown vs. those that would favor synthesis of these energy stores (include what is going on in different organs). Glycogen can be synthesized from, or broken down to Glucose 1P. Similarly, Fatty acids can be synthesized from, or broken down to Acetyl CoA. Explain why, in each case, both the breakdown and synthesis pathways are energetically favorable. You do not need to write the whole pathway, just succinctly summarize key features that change the overall energetics of biosynthetic vs. the breakdown pathways to make both directions favorable.
In: Chemistry