Which of the following is a physical change: a. turning solid sodium to and chlorine gas to salt
b. forming a mixture
c. food turning into waste in the intestines
d. burning wood

7. what temperature is need to just dissolve 50 g of nh4cl in 75 g of water? '

What term is missing from the central region that describes hypotheses, theories, and laws? popular predictable mathematical falsifiable

Ageochemist examines a piece of metal that he found in the soil. he performs tests to identify the metal from its density, electrical conductivity, and melting point. which statement best describes his investigation? a. he is determining physical properties that are sufficient to identify the metal. b. he is determining chemical properties that are sufficient to identify the metal. c. he is determining physical properties that are insufficient to identify the metal. d. he is determining chemical properties that are insufficient to identify the metal.