CHM 2045 Lecture Notes - Lecture 3: Calcium Nitrate, Molecular Mass, Chemical Formula

• School: University of Florida
• Department: Chemistry
• Course: CHM 2045
• Professor: Martina Sumner

Document Summary

Nacl: mass (g) of nacl = (mass of na) + (mass of cl) = 23 + 35. 45 = 58. 45 g nacl. Calcium nitrate: find the chemical formula, find mass. Mass (g) of cano3 = (mass of ca) + (mass of n) + (mass of o *3) = 40. 078 + 14. 0067 + (15. 999 * 3) = 372. 5 g cano3. Converting between amount, mass, and number of chemical entities: ex. How many g is 2. 3 moles of water: 2. 3 moles h2o * (18 g h2o / mole) = 41. 4 g h2o. G -> moles: cancel out grams by putting the molar mass of the compound to cancel out the grams and leave you with moles for your final answer. Moles -> g: do the opposite of g->moles except cancel out moles. Moles to moles: set up the molar ratio (the small number below the element) Mass percent of n = ((3*14. 0067 g) / (149. 09 g)) * 100.