Which form of decay produces a nucleus similar to the element helium? alpha particle

beta particle

gamma ray

Which best describes how johannes kepler developed his laws of planetary motion

Concentrations expressed as a percent by mass are useful when the solute is a a. liquid b. gas c. solid

When hydrogen peroxide (h2o2) is added to potassium iodide (ki) solution, the hydrogen peroxide decomposes into water (h2o) and oxygen (o2). the chemical equation for the decomposition reaction is: 2h2o2—> 2h2o + o2. what is the role of the potassium iodide in this reaction? a. reactant. b. product. c. precipitate. d. catalyst.