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Type the correct answer in the box. Express the answer to three significant figures.

Given:
CH4 + 2O2 → CO2 + 2H2O, ΔH = -890 kJ/mol

How much energy is released when 59.7 grams of methane (CH4) reacts with oxygen?

The combustion of 59.7 grams of methane releases kilojoules of energy.

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? a. the balloons both rise. the cold balloon is larger than the warm balloon. b. the balloons rise at the same rate. both balloons are the same size. c. the warm balloon expands and rises. the cold balloon shrinks and sinks. d. the cold balloon expands and rises. the warm balloon shrinks and sinks.

How does the motion of particles in a gas change as the gas cools

Abeaker with 2.00×102 ml of an acetic acid buffer with a ph of 5.000 is sitting on a benchtop. the total molarity of acid and conjugate base in this buffer is 0.100 m. a student adds 4.70 ml of a 0.360 m hcl solution to the beaker. how much will the ph change? the pka of acetic acid is 4.740.