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Carefully examine the following reaction sequence for the catalytic formation of ozone, O 3, from molecular oxygen, O 2. Which chemical compound is behaving as the catalyst?  O 2 + 2 NO → 2 NO 2  2 NO 2 → 2 NO + 2 O  2 O + 2 O 2 → 2 O 3

When  Ra decays by emitting an alpha particle, what is the atomic number of the resulting nucleus? What is the resulting atomic mass?

According to the following balanced chemical equation, if you want to generate two moles of H 2O, how many molecules of O 2 do you need? 2 H 2 + O 2 → 2 H 2O

Use the bond energies below to determine whether the following reaction is exothermic or endothermic: question physical science II.png

Why is the combination of two protons and two neutrons stable, but two protons and one neutron is not?

Of the three sciences, physics, chemistry, and biology, the most complex is

Balance the following equation. ________ NO → ________ N 2O + ________ NO 2

The diagram shows a planet at four positions in its orbit. At which position does it have the greatest gravitational potential energy?

The diagram represents energy levels in a hydrogen atom. The labeled transitions (A through E) represent an electron moving between energy levels. Which labeled transition represents an electron that absorbs a photon with 10.2 eV of energy?

Continents are stationary.