Consider the combustion of ethylene: C2H4(g)+3O2(g)→2CO2(g)+2H2O(g)C2H4(g)+3O2(g)→2CO2(g)+2H2O(g) Part A: If the concentration of C2H4C2H4 is decreasing at the rate of 3.8×10−2 M/sM/s , what is the rate of change in the concentration of CO2CO2? Express the rate in molarity per second to two significant digits   Part B: What is the rate of change in the concentration of H2OH2O? Express the rate in molarity per second to two significant digits.   Part C: Consider the following reaction: N2H4(g)+H2(g)→2NH3(g)N2H4(g)+H2(g)→2NH3(g) If the rate of decrease for the partial pressure of N2H4N2H4 in a closed reaction vessel is 76 torr/h, what is the rate of change for the partial pressure of NH3NH3 in the same vessel? Express the rate in torrs per hour to two significant digits.   Part D: What is the rate of change of total pressure in the vessel during the reaction? Express the rate in torrs per hour to two significant digits.

A zero order reaction has a constant rate of 3.1 × 10−4 mol·L−1·s−1. If after 60 seconds the concentration has dropped to 4.7 × 10−2 mol·L−1, what was the initial concentration (in mol·L−1)? Express your answer to two significant figures.

Consider the reaction: H2 (g) +I2 (g) → 2 HI (g) A chemist performed an experiment and monitored the concentration of I2 during the course of the reaction. The red line in the graph below represents the results obtained. Which line in the plot would best represent how the concentration of HI changes during the course of the reaction? Time (s) Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a a b b d d е е Concentration (M)

Peroxynitric acid (HOONO2) is an unstable molecule that decomposes to nitric acid and oxygen: 2HOONO2(aq) → 2HNO3(aq) + O2(g)When the concentration of peroxynitic acid is graphed against time, the resulting plot is curved, but if the logarithm of this concentration is plotted, we instead get a straight line. Based on this, which statement is true? a)  This decay is a second order in peroxynitric acid. b)  The slope of the straight-line graph is the rate constant. c)  One needs the concentration of peroxynitric acid to calculate its half-life. d)  The rate law appears to be of the form -Δ[HOONO2]/Δt = k[HOONO2].

1a

Aluminum will slowly react with oxygen to produce aluminum oxide. The rate of this reaction has been measured for two different reaction conditions. The rate is 4 mmol/s when 2 M Al is reacted with 3 M O, and the rate is 2 mmol/s when 1 M Al is reacted with 3 M O. What would be the value of M for the rate equation, rate = k [Al]^m[O}^n

Assume that the formation of nitrogen dioxide, 2 NO(g) + 02(g) – 2 NO2(g) is an elementary reaction. (a) Write the rate law for this reaction. (Rate expressions take the general form: rate = k. [A]ª . [B]b.) chemPad О Help Greek - rate=k•[NO]2.[02] rate=k*[NO]^2*[O_2] Correct. (b) A sample of air at a certain temperature is contaminated with 1.9 ppm of NO by volume. Under these conditions, can the rate law be simplified? If so, write the simplified rate law. If not, repeat your answer from above. (Rate expressions take the general form: rate = k . [A]ª . [B]b. Use k' for the new rate constant as needed.) chemPad O Help Greek - rate=k':[NO]2 rate=k*[NO]^2 Correct. (c) Under the conditions described in (b), the half-life of the reaction has been estimated to be 6.7x103 min. What would the half-life be if the initial concentration of NO were 12.4 ppm? 4.0 |1030192 X min Supporting Materials Periodic Table Constants and E Supplemental Data

A metal cube dissolves in acid such that an edge of the cube decreases by 0.60 ​mm/min. How fast is the volume of the cube changing when the edge is 7.70 ​mm?

In the laboratory, hydrogen gas of good purity can most easily be obtained by the reaction of a strong acid, like sulfuric acid, on a reactive metal, such as zinc: Zn(s)+H,SO,(aq) ZnSO,(aq)+H, (g) Suppose an engineer decides to study the rate of this reaction. He prepares four reaction vessels by adding 160.9 g of solid zinc and 83. mL of 5.0 M sulfuric acid solution to each, and then filling the remainder of the vessel with distilled water. The volume and temperature of each vessel is shown in the table below. Arrange the reaction vessels in decreasing order of initial rate of reaction. In other words, select a "1" next to the vessel in which the engineer can reasonably expect the initial rate of reaction to be highest, a "2" next to the vessel in which the initial rate of reaction would be next highest, and so on. alo Ar initial rate of vessel volume temperature reaction A 1.0 L 14.0 °C В 4.0 L 14.0 °C ? 2.0 L 14.0 °C 8.0 L 14.0 °C v ? 1 (highest) 2 4 (lowest) >

Coal gasification produces an easily-transportable, clean-burning combination of carbon monoxide and hydrogen from coal by reacting it with steam, like this: C(s) + H₂O(g) → CO(g) +H₂(g) Suppose an engineer decides to study the rate of this reaction. He prepares four reaction vessels with 95.1 g of solid carbon and 12.3 g of steam each. The volume and temperature of each vessel is shown in the table below. Arrange the reaction vessels in decreasing order of initial rate of reaction. In other words, select a "1" next to the vessel in which the engineer can reasonably expect the initial rate of reaction to be highest, a "2" next to the vessel in which the initial rate of reaction would be next highest, and so on. vessel volume temperature A B C D 4.0 L 2.0 L 4.0 L 2.0 L 300, "C 310, "C 310 °C 330. "C X initial rate of reaction P ? ? ? G v V