physical change\n1. a change in size, shape, or state\n2. no new substance is formed.\n\nchemical change\n1…

physical change\n1. a change in size, shape, or state\n2. no new substance is formed.\n\nchemical change\n1. a change in the physical and chemical properties\n2. a new substance is formed.\n\nidentify the following as physical (p) or chemical (c) changes.\n1. nacl (table salt) dissolves in water.\n2. ag (silver) tarnishes.\n3. an apple is cut.\n4. heat changes h₂o to steam.\n5. baking soda reacts to vinger.\n6. fe (iron) rusts.\n7. alcohol evaporates.\n8. ice melts.\n9. milk sours.\n10. sugar dissolves in water.\n11. wood rots.\n12. pancakes cook.\n13. grass grows.\n14. a tire is inflated.\n15. food is digested.\n16. paper towel absorbs water.

Answer

Explanation:

Step1: Recall physical - chemical change definitions

Physical change involves size, shape, or state change with no new substance. Chemical change forms a new substance.

Step2: Analyze NaCl dissolving in water

NaCl dissolving in water is a physical change as it just disperses in water without forming a new substance. So it's P.

Step3: Analyze silver tarnishing

Silver tarnishing is a chemical change as silver reacts with sulfur - containing compounds in air to form silver sulfide (a new substance). So it's C.

Step4: Analyze an apple being cut

Cutting an apple is a physical change as it only changes the shape and size of the apple, no new substance is formed. So it's P.

Step5: Analyze water turning to steam

Heating water to steam is a physical change as it's a state change from liquid to gas without forming a new substance. So it's P.

Step6: Analyze baking - soda reacting with vinegar

Baking soda reacting with vinegar is a chemical change as carbon dioxide gas, water, and a salt are formed (new substances). So it's C.

Step7: Analyze iron rusting

Iron rusting is a chemical change as iron reacts with oxygen and water to form iron oxide (rust, a new substance). So it's C.

Step8: Analyze alcohol evaporating

Alcohol evaporating is a physical change as it changes from liquid to gas without forming a new substance. So it's P.

Step9: Analyze milk souring

Milk souring is a chemical change as bacteria ferment lactose in milk to form lactic acid (a new substance). So it's C.

Step10: Analyze sugar dissolving in water

Sugar dissolving in water is a physical change as it just disperses in water without forming a new substance. So it's P.

Step11: Analyze wood rotting

Wood rotting is a chemical change as microorganisms break down the complex organic compounds in wood into simpler substances (new substances). So it's C.

Step12: Analyze pancakes cooking

Pancakes cooking is a chemical change as the heat causes chemical reactions in the batter like the Maillard reaction, forming new substances with different flavors and textures. So it's C.

Step13: Analyze grass growing

Grass growing is a chemical change as photosynthesis and other biochemical processes occur to build new plant tissues (new substances). So it's C.

Step14: Analyze inflating a tire

Inflating a tire is a physical change as it just changes the volume of the tire by adding air, no new substance is formed. So it's P.

Step15: Analyze food digesting

Food digesting is a chemical change as enzymes break down large food molecules into smaller ones (new substances). So it's C.

Step16: Analyze paper towel absorbing water

Paper towel absorbing water is a physical change as it's just a capillary - action process without forming a new substance. So it's P.