A student added 5 grams of calcium chloride, a white solid substance, to 15 grams of water at 22° C. Several observations were made and the student inferred that a chemical reaction occurred.
Which observation best supports the student's inference that a chemical reaction occurred?

On a distance vs time graph the line of an object at rest is a

Based on the equation and the information in the table, what is the enthalpy of the reaction?

Oxidation-reduction reactions (often called "redox" for short) are reactions that involve the transfer of electrons from one species to another. oxidation states, or oxidation numbers, allow chemists to keep track of these electron transfers. in general, one element will lose electrons (oxidation), with the result that it will increase in oxidation number, and another element will gain electrons (reduction), thereby decreasing in oxidation number. the species that is oxidized is called the reducing agent or reductant. the species that is reduced is called the oxidizing agent or oxidant. to sum up: oxidation = increase in oxidation state = loss of electrons = reducing agent reduction = decrease in oxidation state = gain of electrons = oxidizing agent part a which element is oxidized in this reaction? fe2o3+3co→2fe+3co2 enter the elemental symbol. view available hint(s) is oxidized part b which element is reduced in this reaction? 2hcl+2kmno4+3h2c2o4→6co2+2mno2+2kcl +4h2o enter the elemental symbol. view available hint(s) is reduced