What happens when a pure substance undergoes a chemical change

What is the correct definition of force? moving an object slowing down a push or a pull speeding up

A student dissolves 3.9g of aniline (C6H5NH2) in 200. mL of a solvent with a density of 1.05 g/mL. The student notices that the volume of the solvent does not change when the aniline dissolves in it.

Compute the mass of caso4 that can be prepared by the reaction of 3.2900g of h2so4 with 3.1660g of caco3

Which of the following is not an example of a mineral crystal shape? A. Pyrite B. Calcite C. Kryptonite D. Quartz

The burning of fossil fuels for energy in the modern era of life on earth is resulting in a significant increase in total co2 concentration in earth's atmosphere. however, the ratio of 14c to 12c is decreasing. why is this?

Which gas is not a greenhouse gas, A methane, B Water Vapor, C, Carbon dioxide, D, Nitrogen, E, Ozone

A very small equilibrium constant means ... a. an equal amount of reactants and products c. more products b. more reactants d. system isn't at equilibrium

What is in a banana? give me specifics?!

When 17.28 mL of a 0.078 M aqueous solution of Na2SO4 is combined with 11.30 mL of a 0.20 M aqueous solution of NaCl and 7.84 mL of a 0.26 M aqueous solution of KCl, what is the total concentration of Na + in the combined solution?

What mass of carbon can 3000 J of energy raise from 12°C to 40°C?