A sample of coal is found to contain 68.2% carbon and 24.3% ash (by weight) the rest is moisture. The refuse obtained at the end of combustion is analyzed to contain 8.1% carbon and the rest ash. Compute the percentage of original carbon remaining unburnt in the refuse.

A 5.00 gram sample of dry ice (solid CO2) is placed in an evacuated container whose temperature is held constant at -70.0 C. If the sublimation temperature of dry ice is -78.4 C, and if its heat of sublimation is 25.13 kJ/mol, then: a) identify the system b) identify the surroundings c) write a balanced equation showing phases d) compute the enthalpy change of the system e) compute the entropy change of the system f) compute the entropy change of the surroundings g) compute the entropy change of the universe

A fuel composed entirely of methane (CH4) and nitrogen (N2) is burned withexcess air. The flue gases analyze 7.5% CO2, 7% O2 and the remainder, N2. Calculate:(a) percentage of excess air(b) analysis of fuel gas(c) analysis of flue gas (wet basis)

(b) Bayu Hijau is a famous company providing several types of food seasonings. In one of their mixing operation, starch and dried, powdered vegetables will be mixed in a batch mixer with the initial proportions of dried vegetable to starch were 40:60. The variance of the sample compositions measured in terms of fractional compositions of starch was found to be 0.0815 after 300 s of mixing. [Bayu Hijau adalah syarikat terkenal yang menyediakan beberapa jenis perasa makanan. Dalam salah satu operasi pencampuran mereka, pati dan sayur-sayuran kering dan tepung akan dicampurkan dalam kumpulan pengadun dengan perkadaran awal sayur-sayuran kering hingga pati adalah 40:60. Varians komposisi sampel yang diukur dari segi komposisi pecahan pati didapati 0.0815 setelah 300 s pencampuran.] i. Assume that the starch and the vegetable particles are of approximately the same physical size and that a sample contains 24 particles. Calculate the duration of the mixing to continue to reach the specified…