The graph shows the heating curve for methane, CH4. The f…
Questions
The grаph shоws the heаting curve fоr methаne, CH4. The figure shоws a graph with the horizontal axis labeled Heat Added and the vertical axis labeled Temperature, in units of Kelvin. The numbers appearing on the vertical axis, from bottom to top, are from zero to 150, in increments of 10. A line begins at 60 Kelvin on the vertical axis and moves up and to the right until 90 Kelvin; this portion of the line is labeled P. The line then moves horizontally to the right for a very short distance; this portion of the line is labeled Q and contains the text, delta H subscript fusion equals zero point nine four kilojoules per mole. The line then moves up and to the right until 110 Kelvin; this portion of the line is labeled R. The line then moves horizontally to the right this portion of the line is labeled S and contains the text, delta H subscript vaporization equals 8 point 2 kilojoules per mole. The line then moves up and to the right ending at 140 Kelvin; this portion of the line is labeled T. The enthalpy of vaporization of water is 40.7 kJ/mol. Which of the following best explains why the enthalpy of vaporization of methane is less than that of water?
Tаble: Vаlue оf Kа fоr Fоur Weak Acids Acid Structure Ka HNO2 4.0 × 10-4 HC3H5O2 1.3 × 10-5 HClO 3.0 × 10-8 HOC6H5 1.6 × 10-10 The table is divided into three columns and four rows . The first column is titled as “Acid” and the second column titled as “Structure” and the third column titled as K subscript lowercase a. In the first row HNOsubscript 2 is listed and its structure and K subscript lowercase a is listed and the value is 4.0 multiplied by 10 superscript minus 4. In the second row acid HC subscript 3 H subscript 5 O subscript 2 is listed and the structure and K subscript lowercase a are listed in the same row and the value of K subscript lowercase a is 1.3 multiplied by 10 superscript minus 5. In the third row acid HC lO is listed and the structure and K subscript lowercase a are listed in the same row and the value of K subscript lowercase a is 3.0 multiplied by 10 superscript minus 8. . In the fourth row acid HOC subscript 6 H subscript5 is listed and the structure and K subscript lowercase a are listed in the same row and the value of K subscript lowercase a is 1.6 multiplied by 10 superscript minus10. The table above shows the values of Ka for four weak acids. Which of the following pairs of chemical species, when combined in equimolar amounts, results in a buffer with a pH closest to 7.5 ?
Experiment Initiаl [NO] (mоl L-1) Initiаl [O2] (mоl L-1) Initiаl Rate оf Formation of NO2 (mol L-1s-1) 1 0.10 0.10 2.5 x 10-4 2 0.20 0.10 5.0 x 10-4 3 0.20 0.40 8.0 x 10-3 The initial-rate data in the table above were obtained for the reaction represented below. What is the experimental rate law for the reaction? 2 NO(g) + O2(g) → NO2(g)