A calorimeter contains 251 g of water at 24.3 C. The temperature of the water decreases to 18.5 C when 12.5 g of potassium nitrate is dissolved in water. Is dissolving potassium nitrate in water endothermic or exothermic

Asample of the male sex hormone testosterone, c19h28o2, contains 3.88×10^21 atoms of hydrogen.(a) how many atoms of carbon does it contain? (b) how many molecules of testosterone does it contain? (c) how many moles of testosterone does it contain? (d) what is the mass of this sample in grams?

Write a brief passage describing a neutral atom of nitrogen-14 (n-14). describe the number of protons, neutrons, and electrons in the atom, where each type of particle is located, and how the terms atomic number, mass number, and atomic mass are related to the particles. use the periodic table to you. 14 protons and eletrons since its a neutral atom

Describe the difference between a. a hypothesis and a theory and b. an observation and an experiment.