Cesium-137 undergoes beta decay and has a half-life of 30.0 years. How many beta particles are emitted by a 14.0-g sample of cesium-137 in three minutes?
A) 6.1 1013
B) 6.2 1022
C) 8.4 1015
D) 1.3 10-8
E) 8.1 1015
Question 2
Calcium hydride (CaH2 ) reacts with water to form hydrogen gas: CaH2 (s) + 2H2O (l) Ca(OH)2 (aq) + 2H2 (g) How many grams of CaH2 are needed to generate 48.0 L of H2 gas at a pressure of 0.995 atm and a temperature of 32 C?
A) 56.8
B) 0.954
C) 161
D) 40.1
E) 80.3
Question 3
Complexes containing metals with d10 electron configurations are typically colorless because ________.
A) there is no d electron that can be promoted via the absorption of visible light
B) the empty d orbitals absorb all of the visible wavelengths
C) there are no d electrons to form bonds to ligands
D) a complex must be charged to be colored
E) d electrons must be emitted by the complex in order for it to appear colored
The life cycle of a flowering plant.
Model of a sequential study in which two cohorts were followed beginning at age 20. One cohort was f
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