The molality of a solution that is made by dissolving a certain mass of ethanol in 85.4 g of water is 0.950 m. how many moles of ethanol were dissolved?

0.0811 mol
0.0899 mol
11.1 mol
81.1 mol

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

Given the following at 25c calculate delta hf for hcn (g) at 25c. 2nh3 (g) +3o2 (g) + 2ch4 (g) > 2hcn (g) + 6h2o (g) delta h rxn= -870.8 kj. delta hf=-80.3 kj/mol for nh3 (g), -74.6 kj/mol for ch4, and -241.8 kj/mol for h2o (g)