A hot air balloon of 257m^3 is made from 8.50kg of materials. The outside atmosphere is 1.00 atm, and 18C and pure N2 atmosphere. CH4 + 2 O2 --> CO2 + 2H2O dHrxn = -890 kJ
All heat from CH4 burning goes into all the air originally in the balloon before heating
SN2 = 0.55 J/gC

What mass in grams of CH4 needed to be burned to achieve neutral buoyancy?

In apex! a liquid heated beyond a certain temperature becomes

Two metal blocks that have slightly different temperatures are placed next to one another. after five minutes, they both have lower but equal temperatures. according to the law of conservation of energy, what  most likelyhappened? energy was created inside the blocks.energy was destroyed inside the blocks.energy was absorbed into the blocks from outside the system.energy was transferred from the warmer block to the cooler block.

Predict the relative bond lengths of the three carbon-oxygen bonds in the carbonate ion (co2−3). what would you expect the charge to be on each oxygen? match the words in the left column to the appropriate blanks in the sentences on the right. make certain each sentence is complete before submitting your answer.