Which best describes how an ionic bond forms? A. Two molecules share an electron. B. One atom pulls an electron from another atom. C. Two atoms share valence electrons. D. Two atoms both lose an electron.

Which of the following causes water from deep currents to rise to the surface to replace warm currents? a. the flow of warm currents from the equator toward the poles b. freezing of the surface of the water c. increased salinity due to evaporation d.

Which of these is a example of a chemical reaction that occurs at a very fast rate A. Rotting Wood B. An Explosion C. Photosynthesis D. Iron Rusting

As you move left to right across a period, which of the following always increases

Why are pennies good for simulating radioactive atoms? Check all that apply

Identify the Brønsted-Lowry acid, the Brønsted-Lowry base, the conjugate acid, and the conjugate base in each reaction: (a) (CH3) 3N (aq) + H2O (l) ⇌ (CH3) 3NH + (aq) + OH - (aq) (b) HNO3 (aq) + H2O (l) ⇌H3O + (aq) + NO3 - (aq) Drag the appropriate

Assume 3 molecules of Fe react according to the following equation. 3Fe + 4H2O Fe3O4 + 4H2 How many molecules of H2 are produced? How many water molecules are required? What is the mole ratio of Fe to H2O?

10.0 mL of a HF solution was titrated with a 0.120 N solution of KOH; 29.6 mL of KOH were required to completely neutralize the HF. Calculate the normality of the HF solution.

The number of grams present in 1.35 mol of Fe is

Which can associate a suspect's gun with a crime?

In which era did the first fish appear? a. Carboniferous b. Paleozoic C. Mesozoic d. Permian