The amount of i−3(aq)i3−(aq) in a solution can be determined by titration with a solution containing a known concentration of s2o2−3(aq)s2o32−(aq) (thiosulfate ion). the determination is based on the net ionic equation 2s2o2−3(aq)+i−3(aq)⟶s4o2−6(aq)+3i−( aq) 2s2o32−(aq)+i3−(aq)⟶s4o62−(aq)+3i−( aq) given that it requires 25.2 ml25.2 ml of 0.470 m na2s2o3(aq)0.470 m na2s2o3(aq) to titrate a 10.0 ml10.0 ml sample of i−3(aq),i3−(aq), calculate the molarity of i−3(aq)i3−(aq) in the solution.

Lem 2 the data below are for the system ethyl propyl ether (1)-chloroform (2) at 0.5 bar. use the data to answer the following questions (all questions refer to p d 0: 5 bar). a) what are the boiling points of the pure components at 0.5 bar? b) a mixture with the overall composition z1 d 0: 1 is brought to 47.6ä±c, 0.5 bar. what is the phase? c) 100 mole of a mixture with z1 d 0: 1 (state a) is mixed with 22 mole of pure ethyl propyl ether vapor (state b). the mixing takes place at 47.6 ä±c, 0.5. bar. what is the phase of the resulting mixture (state c)? if the state is a v/l mixture report the number of moles and mole fractions in each phase. d) plot the txy graph and show states a, b and c. the graph must be done by computer and should be properly annotated. ethyl propyl ether (1) - chloroform (2) at 0.5 bar t ( ä±c) x1 y1 t ( ä±c) x1 y1 42.9 0.000 0.000 49.0 0.470 0.455 43.0 0.020 0.010 49.1 0.520 0.520 43.9 0.065 0.029 48.9 0.567 0.592 45.4 0.156 0.089 48.3 0.652 0.720 46.4 0.215 0.142 47.6 0.745 0.815 47.6 0.296 0.223 46.7 0.822 0.872 48.3 0.362 0.302 45.7 0.907 0.937 48.7 0.410 0.375 44.6 1.000

The characteristic of two different types of reactions are shown below. reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of and element. which statement is true about the atoms of the elements that participate in the two reactions? a: their identity changes in both reaction a and b. b: their identity changes in reaction a but not b. c: their identity changes in reaction b but not a. d: their identity remains the same.

What mass of natural gas (ch4) must you burn to emit 276 kj of heat?