The original substance in a

chemical reaction; either

disappears or diminishes

A scientist found a new species in a rain forest. The species was small and green in color. She examined one of its many cells and found that the cell had a nucleus but no cell wall.

In the reaction K2CrO4 (aq) + PbCl2 (aq) 2KCl (aq) + PbCrO4 (s), how many grams of PbCrO4 will precipitate out from the reaction between 25.0 milliliters of 3.0 M K2CrO4 in an excess of PbCl2?

Which of the following is the best definition of a scientific theory? A predicted experimental outcome A mathematical model (an equation) A prediction of how a natural phenomenon will behave A well tested explanation of a natural phenomenon

Calculate the pH of a solution if the concentration of hydronium ions (H3O+) is 4.8 x 10-11M?

A compound has been shown to contain 14.5 percent hydrogen and 85.5 percent carbon by mass. Choose the most informative and correct statement that can be made about the compound on the basis of the data given. Select one: a.

What is the molarity of a solution containing 5.0 moles of kcl in 2.0 l of solution?

Compare the electron configurations of hydrogen, lithium, and sodium. Why do you think these elements are grouped in the same family?

What is the theoretical yield of silver chloride?

Calculate the cell potential for the galvanic cell in which the reaction Fe (s) + Au 3 + (aq) - ⇀ ↽ - Fe 3 + (aq) + Au (s) occurs at 25 ∘ C, given that [ Fe 3 + ] = 0.00150 M and [ Au 3 + ] = 0.797 M.

Magnesium is lighter than other structural metals, so it is increasingly important in the design of more efficient vehicles.