1. Which property could be a chemical property of hydrogen? a. It is a gas.
b. It is colourless.
c. It can explode and burn in the presence of air.

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.

The reactions of photosynthesis occur in the of plant cell? a. mitochondria. b. lysosomes. c. chloroplasts. d. chlorophyll

I’m an electrically neutral atomic any element, there are equal numbers of