In 1961 the mlar atomic mass of carbon 12 was defined to be exactly 12g/mol (a value agreed upon by chemists and physicists) and the molar atomic masses of all the elements were re-evaluated according to this new standard. this made the re-evaluated molar mass of oxygen-16 become 15.994915g/mol. avogadro's number is defined as the number of atoms in the molar atomic mass of an element. the present accpted value for avogadros' number is 6.0221367x10^23/mol. what was the value o avogadro's number used by physicists before 1961? .

Which statement best describes how private industry decides where to spend the money on research and development

Simon is writing a story about an astronaut whose spacecraft has been boarded by space pirates. the astronaut has her lucky penny in her hand behind her back as the space pirates break into the control room. she has just locked the controls so that the ship is accelerating in the direction of the control room’s ceiling. simon wants the astronaut to use the penny to hit a button on the control panel to turn off the lights and escape. the button is located a short distance behind and below the astronaut’s hands. how should simon use the theory of relativity to describe what the astronaut must do in order to hit the button?

Diverging mirrors and lenses always produce images