What did early scientists assume that the polar caps had in common?

The first step is in oil is what

Which of the following statements is true? Kinetic energy depends on mass, gravity, and speed. All machines lose some energy because of friction. Heat lost during work is easily recovered and used for useful actions.

You and a friend are looking at the stars and your friend says, "Stars must be shrinking because gravity is constantly pulling their particles together." Explain what is wrong with this reasoning.

Describe one main use for each fuel:coal, oil, and natural gas

3 Ni2 + (aq) + 2 Cr (OH) 3 (s) + 10 OH - (aq) → 3 Ni (s) + 2 CrO42 - (aq) + 8 H2O (l) ΔG∘ = + 87 kJ/molGiven the standard reduction potential of the half-reaction Ni2 + (aq) + 2 e - → Ni (s) E∘red = - 0.

N an exothermic reaction, what is true of the enthalpy? A. It has increased. B. It has decreased. C. It has remained unchanged. D. It has, at minimum, doubled.

Which of the following is not a property of a metal? Luster Malleability Permeability Ductility

Ki+cl2 Kcl + I2 Chemical reactions

When the ph of the extracellular fluid declines, the kidneys?

What is created when combustion happens without enough oxygen? a. carbon dioxide b. water c. coal d. soot