alka - seltzer gives off carbon dioxide when added to water. *\nthis is a physical change\nthis is a…

alka - seltzer gives off carbon dioxide when added to water. *\nthis is a physical change\nthis is a chemical change\nsodium and potassium react violently with water. *\nthis is a physical change\nthis is a chemical change\nwater is absorbed by a paper towel. *\nthis is a physical change\nthis is a chemical change

alka - seltzer gives off carbon dioxide when added to water. *\nthis is a physical change\nthis is a chemical change\nsodium and potassium react violently with water. *\nthis is a physical change\nthis is a chemical change\nwater is absorbed by a paper towel. *\nthis is a physical change\nthis is a chemical change

Answer

Brief Explanations:

  1. When Alka - Seltzer reacts with water and gives off carbon dioxide, new substances are formed. A chemical change involves the formation of new substances through chemical reactions, so this is a chemical change.
  2. When sodium and potassium react with water violently, new substances are produced in the reaction. Thus, it is a chemical change.
  3. When water is absorbed by a paper towel, no new substances are formed. The water is just physically moved from one place to another within the paper towel's pores. This is a physical change.

Answer:

  1. This is a CHEMICAL change
  2. This is a CHEMICAL change
  3. This is a PHYSICAL change