Which reaction is exothermic?

CH4 + 2O2 - - >CO2 + 2H2O + 891 kJ

NH4NO3 + H2O + 25 kJ - - > NH4 + (aq) + NO3 - (aq)

2H2O + 286 kJ - - > 2H2 + O2

N2 + O2 + 181 kJ-->2NO

What is the ratio of Al 3 + ions to S 2 - ions in a neutral compound?

Which statement is true? Select one: a. Hydroelectric power, a nonrenewable resource, is generated from moving water. b. Oil, a nonrenewable resource, is processed to make jet fuel. c. Propane, a renewable resource, is used in some heating systems.

Which of the following is used to separate the parts of mixtures a. Atomic number. B. Physical properties. C. Microscopes. D. Burning

Atp production in the flight muscle of the fly lucilia sericata results almost exclusively from oxidative phosphorylation. during flight, 187 ml of o2/hr·g of body weight is needed to maintain an atp concentration of 7.0 μmol/g of flight muscle.

32P can be used to make any nucleotide (A, C, G, or T) radioactive. Which of the following explains why this is true? A. All nitrogenous bases have a phosphorus atom that can be replaced with 32P. B.

Every water molecule has two hydrogen atoms bonded at one oxygen atom. This fact supports the concept that elements in a compound are

What is the mass of 9 atom (s) of copper in grams?

Andy has two samples of liquids. Sample A has pH of 4, and sample B has a pH of 6. what can Andy conclude about these two samples? Sample A is a neutral b alkali c acidic Sample B is a neutral b alkali c acidic

How does a lone pair contribute to molecular shape? A. It is too small to affect the molecule's shape. B. It takes up space like an "invisible" atom. C. It forces the molecule into a tetrahedral shape. D. It lets the bonding pairs spread out more.

The are of a rectangle is 12 in^2. what is the area in cm^2. there are 2.54cm in an inch.