The two most abundant elements in earth's core are ?

Write the chemical formula for a compound that is made of an element from group 1 and an element from group 17

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.

Problem page a jet airplane reaches 846. km/h on a certain flight. what distance does it cover in 13.0 min? set the math up. but don't do any of it. just leave your answer as a math expression. also, be sure your answer includes all the correct unit symbols.