What is the number of orbit for calcium

Ageologist determines that a sample of a mineral can't be scratched by a steel nail but can be scratched by a masonry drill bit. based on this information, the sample mineral has to be softer than a. orthoclase. b. fluorite. c. apatite. d. corundum.

What is the mass of 2.00 l of an intravenous glucose solution with a density of 1.15 g/ml?

How many moles of sulfur dioxide are produced when 4.38 moles of oxygen completely react with iron (iv) sulfide