What is the name of the uppermost layer of the atmosphere? why does it feel cold there, even though the temperature can be very high?

One of the hopes for solving the world's energy problem is to make use of the fusion reaction 21h +31h --> 42he + 10n + energy how much energy is released when 1 mol of deuterium is fused with 1 mol of tritium according to the above reaction? the masses of the atoms and the neutrons are as follows: 21h = 2.0140 amu 31h = 3.01605 amu 42he = 4.002603 amu 10n = 1.008665 amu. the speed of light is 2.9979 x 108 m/s.

Structure of the atoms: discovery of the nucleus in 1909i need answering all of these questions

What is the area in square meters of 448 g ai foil that has a thickness of 23921 nm? the density is 2.70 g/cm