Đểnén 10 lít không khí đến thểtích 2 lít, người ta có thểtiến hành theo hai cách:nén đẳng nhiệt hay nén đoạn nhiệt. Hỏi cách nén nào tốn công ít hơn

A175 g lump of molten lead at its melting point (327 c) is placed into 55.0 g of water at 20.0 c. the specific heat of lead is 130.j/kg c and the hf of lead is 20,400 j/kg. when the lead and the water have reached equilibrium, what is the temperature of the mixture?

Exercise 2. find the wavelength of a photon emitted when an electron jumps from the n = 3 energy level down to the n = 2 energy level. where is this photon in the electromagnetic spectrum?

The radius of an atom is closest in size to a