Use the reaction and bond information to answer the question. H2 + CO2 → CH2O2

Reactant bond energies: H–H is 432 kJ/mol, C=O is 799 kJ/mol

Product bond energies: C–H is 413 kJ/mol, C=O is 745 kJ/mol, C–O is 358 kJ/mol, O–H is 467 kJ/mol

How much energy must this system absorb before the reaction can begin?

2,030 kJ

2,462 kJ

1,231 kJ

1,663 kJ

An atom's configuration based on its number of electrons ends at 3p4. another atom has seven more electrons. starting at 3p, what is the remaining configuration? 3p63d34s2 3p43d54s2 3p64s23d3 3p44s23d

Nebulae are enormous clouds in outer space. they are made mostly of hydrogen gas, helium gas, and dust. some nebulae glow brightly, while others do not. the stars that people see are huge, bright balls of glowing gas. they are made mostly of hydrogen and helium. which statement correctly describes other ways in which nebulae and stars are different? a. stars can form inside a nebula but a nebula can never be produced by any star. b. a star always has a higher density than a nebula. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star.

Which sample at stp has the same number of atoms as 18 liters of ne at stp