The propane fuel (C3H8) used in gas barbeques burns according to the following thermochemical equation:C3H8(g)+5O2(g)?3CO2(g)+4H2 O(g)?H?rxn=?2217kJ If a pork roast must absorb 1.7×103 kJ to fully cook, and if only 14 % of the heat produced by the barbeque is actually absorbed by the roast, what mass of CO2 is emitted into the atmosphere during the grilling of the pork roast?
Express your answer using two significant figures. m=g

Calcium chloride +gold(1) oxide—>

Astudent is given a sample of a blue copper sulfate hydrate. he weighs the sample in a dry covered porcelain crucible and got a mass of 23.875 g for the crucible, lid, and sample. the mass of the empty crucible and lid was found earlier to be 22.652 g. he then heats the crucible to expel the water of hydration, keeping the crucible at red heat for 10 minutes with the lid slightly ajar. on colling, he finds the mass of crucible, lid, and contents to be 23.403 g. the sample was changed in the process to very light clue anhydrous cuso4. if there are again 100.0 g of hydrate, how many grams of cuso4 are in it? how many moles of cuso4? (hint: molar mass of cuso4 = 159.6 g / mole. what per cent of the hydrate is cuso4? you may convert the mass of cuso4 to moles.)

Electrons are extremely important to what area of technology? a) anti-aging research b) household product development c) electronics d) drug discovery