Is density a chemical or physical change?

What must be done to the following half-reactions before they can be added together? Mn (s) → Mn 2 + (aq) + 2e - Fe 3 + (aq) + 3e - → Fe (s) Double the Mn half-reaction and triple the Fe half-reaction.

For the reaction? H2 + ? O2 →? H2O, what is the maximum amount of H2O (18.0153 g/mol) which could be formed from 9.43 g of H2 (2.01588 g/mol) and 12.98 g of O2 (31.9988 g/mol) ? Answer in units of g.

Researchers tested a meteorite for organic molecules containing 13C and 15N, which are carbon and nitrogen atoms with one extra neutron.

Which of the following is the change in energy of an atom emitting a photon of wavelength of 4.35 meters? [Planck's constant, h = 6.626 * 10-34 Js, c = 2.998 * 108 meters/second] a) 1.986 * 10-25 joules b) 2.823 * 10-34 joules c) 9.

Homeostasis is maintained by which of the following? Diffusion of molecules from an area of high concentration to lower Osmosis of water into an area of high solute concentration Active transport of molecules to an area of high concentration All of

What organelle does the process of cellular respiration?

How much heat is absorbed during production of 127 g of NO by the combination of nitrogen and oxygen? N2 (g) + O2 (g) →2NO (g), ΔH = + 43 kcal/mol

Which of the following is the result of the process that binds many amino acids on to another? a. protein b. allele c. dna d. rna

What does the electron transport chain do to the concentration of hydrogen ions (protons) ?

What is the cation name for alcl3?