For the reaction 2KlO3 --> 2KCl + 3O2, how many moles of potassium chlorate are required to produce 250 g of oxygen? a. 2.0 mol
b. 5.2 mol
c. 4.3 mol
d. 4.9 mol

Which sentence about particles in matter is true? a. atoms are present in solids and liquids but not in gases. b. the particles of matter are in constant motion. c. the same kinds of atoms are found in different elements. d. when a solid changes to a liquid, the sizes of the particles change.

How many grams of magnesium metal will react completely with 8.3 liters of 5.5m hcl? show all work

Two liquids are poured into a beaker. after a few seconds, the beaker becomes warm. which of the following best describes this reaction? a. an exothermic reaction b. a decomposition reaction c. an endothermic reaction d. a single-displacement reaction