Amajor difference between the two rows of inner transition elements is that the lanthanides
a. are radioactive and the actinides are not
b. occur in nature while most of the actinides are synthetic
c. are gases at room temperature and the actinides are solids
d. have no uses while the actinides have many

Acylindrical specimen of a nickel alloy having an elastic modulus of 207 gpa (30 × 106psi) and an original diameter of 10.2 mm (0.40 in.) experiences only elastic deformation when a tensile load of 8900 n (2000 lbf) is applied. compute the maximum length of the specimen before deformation if the maximum allowable elongation is 0.25 mm (0.010 in.)

Nacidified solution was electrolyzed using copper electrodes. a constant current of 1.18 a caused the anode to lose 0.584 g after 1.52 ✕ 103 s. given that the charge of an electron is 1.6022 ✕ 10−19 c, calculate avogadro's number. assume that copper is oxidized to cu2+ ions.

What are the similarities & differences between a thermistor and a light dependent resistor in physics?