Na2O H2 --> 2Na H2O A student performed the above reaction in the lab, and obtained an actual yield of 3.9 grams of H2O. He calculated a theoretical value of 4.2 grams of H2O. Calculate the percent yield of the reaction.

What is the ima of the 1 st class lever in the graphic given? 2 3 0.5

The atomic radius of sodium is 186 pm and of chlorine is 100 pm. the ionic radius for na+ is 102 pm and for cl– is 181 pm. in going from na to cl in period 3, why does the atomic radius decrease while the ionic radius increases? a. the inner electrons in the sodium cation shield its valence electrons more effectively than the inner electrons in the chloride anion do. b. the inner electrons shield the valence electrons more effectively in the chlorine atom than in the chloride anion. c. the outermost electrons in chloride experience a smaller effective nuclear charge than those in the sodium cation do. d. the outermost electrons in chloride experience a larger effective nuclear charge than those in the sodium cation do. e. monatomic ions are bigger than the atoms from which they are formed.

Use the periodic table to determine the electron configuration of dysprosium (dy) and americium (am) in noble-gas notation.