Is erasing a pencil mark a chemical or physical change?

During the combustion of 2.00 g of coal, the temperature of 500 g of water inside the calorimeter increased from 25.0°c to 43.7°c. the specific heat of water is 4.18 j/g·°c. how much heat did the reaction generate?

Calculate the volume of an object with a mass of 5.45g and a density of 65

What is the equation for the energy levels of the hydrogen atom

14. A neutron has a charge of (1) + 1 (2) + 2 (3) O (4) - 1

What is the relationship between science and pseudoscience?

Which ions are spectator ions in the formation of a precipitate of agcl via combining aqueous solutions of cocl2 and agno3?

Marissa is learning about the unique properties of waves. She has learned that whenever the wavelength of a wave increases, the frequency of the wave decreases.

Which answer choice best explains why uranium-238 can be used in power plants to generate electricity? A) Nuclides of uranium-238 decay over time. They release large amounts of energy as their nuclei break apart.

Explain how you can use physical properties to compare substances.

How is this model useful?