How do mixtures differ from pure substances?

One molecule of chlorophyll contains 137 atoms. how many of these atoms come from the metal magnesium?

A certain radionuclide is used to diagnose lymphoma. An atom of this radionuclide contains 31 protons and 36 neutrons. Which statement is correct about the radionuclide?

Separate this redox reaction into its component half-reactions. 3o2 4co

Hydrogen atoms are excited by a laser to the n = 4 state and then allowed to emit. What is the maximum number of distinct emission spectral lines (lines of different wavelengths) that can be observed from this system?

An object with too many is negatively charged.

0.100 mol of CaCO3 and 0.100 mol CaO are placed in an 10.0 L evacuated container and heated to 385 K. When equilibrium is reached the pressure of CO2 is 0.220 atm. 0.

What is true about the charges of transition metal ions?

A gas obeys the ideal-gas equation of state P V = N k T, where N = n NA is the number of molecules in the volume V at pressure P and temperature T and n is the number of gm-moles of the gas.

76. Which of the following choices is not an example of an adaptation? A. Nocturnal animal species have large eyes. B. One member of a wolf litter is born with shorter legs than its siblings. C.

Which is more dense a pound of rice or a pond of cement