In the reaction of gaseous N₂O₅ to yield NO₂ gas and O₂ gas as shown below the following data table is obtained:

2 N₂O₅ (g) → 4 NO₂ (g) + O₂ (g)

Complete the following three problems:

Using the [O₂] data from the table show the calculation of the average rate over the measured time interval from 0 to 3000 secs.

Using the [O₂] data from the table show the calculation of the instantaneous rate late in the reaction (2400 secs to 3000 secs).

Explain the relative values of the average rate and the late instantaneous rate.

Consider a non-degenerate three level system with E1 < E2 < E3. An intensive incident light of energy hν13 = E3 − E1 is turned on for very short period of time and then turned off. (a) Write down the rate equation for N3(t). (b) Solve this equation. What is the observed radiative lifetime of the excited state corresponding to E = E3?

using the data colleced for part B on your data sheet, calculate the molar mass of the unknown acid. Show Calculations for trial #1 and the average for part B.

Part B Data:

Trial #1 Trial #2 Trial #3   

Mass unknown acid, g: 0.252g 0.250g 0.251g

Final buret reading, mL: 39.1mL 41.5mL 39.1mL

initial buret reading, mL: 2.90mL 2.70mL 2.90mL

volume NaOH used, mL: 36.2mL 38.8mL 36.2 mL

If someone could explain how I'm supposed to figure out the molar mass if i dont know what the formula of the acid to add up the grams is. I was able to do trial #1 for part A of this experiment but I can't do the same things because i am limited on information.

Thanks!

Part A

The change in enthalpy (ΔrHo) for a reaction is -32 kJmol−1 . The equilibrium constant for the reaction is 4.6×103 at 298 K. What is the equilibrium constant for this reaction at 661 K?

Part B

Consider the following reaction: CH3OH(g)⇌CO(g)+2H2(g)

Calculate ΔrG for this reaction at 125 ∘C under the following conditions: PCH3OH= 0.890 bar PCO= 0.145 bar PH2= 0.195 bar

An agricultural runoff diversion system discharges into a small river. The runoff has thefollowing characteristics: flow = 100 m3/min, DO = 3 mg/L, and BOD = 150 mg/L. The riverflows at1000 m3/min and has zero BOD and 9 mg/L of DO. Given that saturation DO is 9.5mg/L, kd is 0.4 day-1, and the ka is 0.7 day-1, calculate the DO and BOD remaining in the stream1.5 days after the discharge event.

150.0 mL of 0.27 M HF with 230.0 mL of 0.32 M NaF Express your answer using two decimal places.

part 1 - A 0.100 M solution of an acid, HA, has a pH=2.00. What is the value of Ka of this acid?

part 2 - We treat Kw as a fixed value, even though it, like all equilibrium constants, varies with temperature. The pH of pure water at 50 oC is 6.630. What is Kw at this temperature?

Molecular Orbital Theory -- Homodiatomics Use the molecular orbital model to fully describe the bonding in O2+, O2, O2-, and O22-. Determine which of the following statements are true and which are false.

The electron configuration of O2- is (σ2s)2(σ2s*)2(σ2p)2(π2p)4(π2p*)

The electron configuration of O2+ is (σ2s)2(σ2s*)2(σ2p)2(π2p)4(π2p*)

The number of unpaired electrons in O2+ and O22- is, respectively, 1 and 2.

The bond lengths increase in the order: O2+ < O2 < O2- < O22-.

The bond order in O2+ and O2 is, respectively, 2.5 and 2.

Bond length and bond energy both increase with increasing bond order.

[Cr(H₂O)₆]²⁺ is violet. Another CrL₆ complex is yellow-green. (Ignore the charge on the complex, Cr remains +2). Which of the following ligands can't be L?

ammine

carbonyl

cyano

hydroxo

nitro

1.

Which of the following statements about nitrogen gas is incorrect ?

Select one:

a. it expands when its temperature is increased at constant pressure

b. the distance between particles is about the same as for liquids

c. the pressure is proportional to the concentration of particles present

d. it expands to fill its container

e. it is less dense than iron

2.

What is the minimum volume of 0.1060 M AgNO₃ that must be reacted with 100.0 mL of 0.0862 M K₂CrO₄ to precipitate all the chromate ions as Ag₂CrO₄?

Select one:

a. 203 mL

b. 163 mL

c. 175 mL

d. 81.3 mL

e. 50.8 mL

3.

What is the pressure of 0.4 moles of gas inside a sealed 5.2 L container at 350 K?

Select one:

a. 22 atm

b. 224 atm

c. 2.2 atm

d. 6052 atm

e. 60 atm

4.

What is the mass % of silver fluoride in a solution prepared by mixing 50.0 g of a 15.0 mass % silver fluoride solution with 23.0 g of an 11.9 mass % silver fluoride solution?

Select one:

a. 20.5%

b. 14.7%

c. 10.2%

d. 13.5%

e. 14.0%

1.Which one of the following species cannot act as a base?

Select one:

a. H₂O

b. Cl^–

c. NH₄⁺

d. OH^–

e. NH₃

_2.

A gas with an empirical formula NO₂ is weighed in a 1 L flask and found to have a mass of 4.0 g. What is its molecular formula? (1 mol of an ideal gas occupies 23.0 L under the conditions of this experiment).

Select one:

a. N₂O₄

b. N₄O₈

c. NO

d. NO₂

e. N₂O

3.

When calcium hydroxide is reacted with excess nitric acid, it produces:

Select one:

a. a solution of Ca²⁺(aq) and OH^–(aq) ions

b. calcium nitrate solution

c. carbon dioxide gas

d. a basic solution

e. hydrogen gas

4.

A dilute aqueous acid was reacted with a white solid to produce a gas. This gas makes limewater turn cloudy and white. Which of the following could be the identity of the white solid?

Select one:

a. NaOH

b. NaHSO₃

c. NaCl

d. NaNO₃

e. NaHCO₃

_5.

When magnesium is reacted with hydrochloric acid, it produces:

Select one:

a. a spark

b. a basic solution

c. carbon dioxide gas

d. a solution containing Mg²⁺ (aq) and Cl^– (aq) ions

e. chlorine gas

1.What values of x,  y and z balance the equation:

x SO₂    +   y H⁺   +    Cr₂O₇^2– → 3 SO₄^2–  + z Cr³⁺ +   H₂O ?

2.What is the stoichiometric ratio of solid phosphorus (P) to chlorine gas (Cl₂) required to give phosphorus trichloride (PCl₃)?

3.What is the mass fraction of carbon in aniline C₆H₅NH₂ expressed as a percentage?

4.

Arrange the following in order of increasing amount of substance:

(i)            24 g of sodium metal
(ii)           40 g of carbon dioxide
(iii)          4 g of hydrogen gas

5.What volume of 0.220 M NaOH(aq) should be used to prepare 303 mL of 2.02 x 10^–3 M NaOH(aq) ?

6.

Gold hydroxide Au(OH)₃ is prepared for electroplating gold by the following reaction

2 KAuCl₄(aq) + 3 Na₂CO₃(aq) + 3 H₂O(l) → 2 Au(OH)₃(s) + 6 NaCl(aq) + 2 KCl(aq) + 3 CO₂(g)

The following amounts are mixed KAuCl₄ = 2.3 mol, Na₂CO₃ = 7.0 mol and H₂O = 10 L.
What is the limiting reagent, and what amount of gold hydroxide is formed if the reaction is ‘stoichiometric’? (M (H₂O) = 18 g mol^–1, ρ(H₂O) = 1.0 kg L^–1)

Select one:

a. Na₂CO₃ , 1.57 mol

b. KAuCl₄ , 4.6 mol

c. KAuCl₄ , 2.3 mol

d. H₂O , 6.9 mol

e. KAuCl₄ , 6.9 mol

7.

What are the chemical formulae for the following acids: nitric acid, acetic acid, hydrochloric acid, sulfuric acid?

Select one:

a. H₂NO₃, CH₃COOH, HClO₂, H₂SO₃

b. HNO₂, CH₃COOH, HCl, HSO₃

c. HNO₃, CH₃CH₂OH, HCl, H₂SO₃

d. HNO₂, CH₃CH₂OH, HClO, H₂SO₄

e. HNO₃, CH₃COOH, HCl, H₂SO₄

I have 5 chemistry questions here.

The Ideal Gas Equation states:

PV = nRT

where "P" equals the pressure of the gas, "V" equals the volume of the container, "n" equals the number of moles of gas in the container, R = the Gas constant (0.082057 L atm K^–1 mol^–1), and "T" equals the temperature of the gas

1. Calculate the volume (in litres) of a sealed container with 5.67 mol of an ideal gas at a temperature of 374.7 K and pressure of 11.15 atm.

2. The temperature is increased by 67.4 K.

Calculate the new pressure of the system (assuming no change in volume).

3. A chocolate bar was found to have 3.5609 kilojoules of chemical energy.

Calculate the number of joules of chemical energy in the chocolate bar.

4. Calculate the number of calories in this chocolate bar.

5.

The pH of a solution is found by the following equation:

pH = –log₁₀[H⁺]

Calculate the pH of a solution with a [H+] of 0.0218 mol L^–1.

a) C₅H₁₂(l) + O₂(g) → CO₂(g) + H₂O(l)

If 28.6 grams of pentane (C₅H₁₂) are burned in excess oxygen, how many grams of H₂O will be produced?

____________g H₂O

b) If baking soda (sodium hydrogen carbonate) is heated strongly, the following reaction occurs:

2NaHCO₃(s) → Na₂CO₃(s) + H₂O(g) + CO₂(g)

Calculate the mass of sodium carbonate that will remain if a 1.28 g sample of sodium hydrogen carbonate is heated

___________  g Na₂CO₃

c) P₂O₅(s) + 3H₂O(l) → 2H₃PO₄(aq)

Given an initial mass of 10.35 g P₂O₅, an excess of H₂O (assuming that all of the reactant is converted to product(s), and none is lost), calculate the mass (g) of H₃PO₄ produced by the reaction.

__________ g

d)

"Smelling salts," which are used to revive someone who has fainted, typically contain ammonium carbonate, (NH₄)₂CO₃. Ammonium carbonate decomposes readily to form ammonia, carbon dioxide, and water. The strong odor of the ammonia usually restores consciousness in the person who has fainted. The unbalanced equation is

(NH₄)₂CO₃(s) → NH₃(g) + CO₂(g) + H₂O(g)

Calculate the mass of ammonia gas that is produced if 1.30 g of ammonium carbonate decomposes completely.

______ g NH₃

Exactly 10.8 ml of water at 31.0 degree celcius are added to a hot iron skilllet. All of the water into converted into steam at 100 degree celcius. The mass of the pan is 1.00kg and the molar heat capacity is 25.19 J/mol degree celcius. What is the temperature change of the skillet?