Answer:
do you have any vocabulary to help you with this or no
Answer is: <span>an atomic radius.
</span>The atomic radius<span> of a </span>chemical element<span> is a measure of the size of its atom.
</span>The atomic radius varies with increasing atomic number, but usually increases because of increasing of number of electrons.
The atomic radius decreases across the periods because an increasing number of protons, because <span>greater attraction between the protons and electrons.</span>
Here we have to compare the Bohr atomic model with electron cloud model.
In the Bohr's atomic model the electrons of an element is assumed to be particle in nature. Which was unable to explain the deBroglie' hypothesis or the uncertainty principle and has certain demerits.
The uncertainty principle reveals the wave nature of the electrons or electron clod model. The Bohr condition of a stable orbits of the electron can nicely be explained by the electron cloud model, the mathematical form of which is λ = nh/mv, where, λ = wavelength, n is the integral number, h = Planck's constant, m = mass of the electron and v = velocity of the electron.
The integral number i.e. n is similar to the mathematical form of Bohr's atomic model, which is mvr = nh/2π. (r = radius of the orbit).
Thus, the electron cloud model is an extension of the Bohr atomic model, which can explain the demerits of the Bohr model. Later it is revealed that the electron have both particle and wave nature. Which is only can explain all the features of the electrons around a nucleus of an element.
A layer of greenhouse gases – primarily water vapor, and including much smaller amounts of carbon dioxide, methane and nitrous oxide – acts as a thermal blanket for the Earth, absorbing heat and warming the surface to a life-supporting average of 59 degrees Fahrenheit (15 degrees Celsius).