How do seismic waves help scientists determine the structures of Earth’s interior? a. Seismic waves travel through different materials at different speeds.
b. Seismic waves carry materials from Earth’s mantle across the Earth and to the surface.
c. Seismic waves activate the Earth’s magnetic field.
d. Seismic waves travel through meteorite remains at different speeds.

Which of the following units is not an official si unit? mole liter kilogram ampere

Which of the following is an indication that a substance has undergone a chemical change? a. no new product has been formed. b. the color of the substance has not changed. c. the original constitute has not changed. d. the molecular structure has changed.

You are attempting to recrystallize a crude product mixture. you add the appropriate amount of hot solvent and are allowing the solution to slowly cool to room temperature. however, at room temperature no crystals have appeared, which of the following methods should be used to induce crystallization? choose all correct answers. a) place the flask in an ice bath. b) swirl the contents of the flask. c) add a small seed crystal of the desired product. d) scratch the inside of the glassware using a stir rod. it can be multiple choices