Answer:
Explanation:
Dmitri Mendeleev developed a chart-like arrangement of the elements called the Periodic Table ______ . He stated that if the elements were listed in order of increasing atomic mass______, their properties repeated in a regular manner. He called this the periodicity of properties ______ of the elements. The arrangement used today differs from that of Mendeleev in that the elements are arranged in order of increasing atomic number______. Each horizontal row of elements is called a(n)period ______. Each vertical column is called a(n) column_____, or , because of the resemblance between elements in the same column, a(n) __group____.
Explanation:
A photon is a quantum of EM radiation. Its energy is given by E = hf and is related to the frequency f and wavelength λ of the radiation by
E=hf=hcλ(energy of a photon)E=hf=hcλ(energy of a photon),
where E is the energy of a single photon and c is the speed of light. When working with small systems, energy in eV is often useful. Note that Planck’s constant in these units is h = 4.14 × 10−15 eV · s.
Since many wavelengths are stated in nanometers (nm), it is also useful to know that hc = 1240 eV · nm.
These will make many calculations a little easier.
All EM radiation is composed of photons. Figure 1 shows various divisions of the EM spectrum plotted against wavelength, frequency, and photon energy. Previously in this book, photon characteristics were alluded to in the discussion of some of the characteristics of UV, x rays, and γ rays, the first of which start with frequencies just above violet in the visible spectrum. It was noted that these types of EM radiation have characteristics much different than visible light. We can now see that such properties arise because photon energy is larger at high frequencies.
Answer:
Explanation:
Hello there!
In this case, considering the Avogadro's gas law, which treats the volume and moles in a directly proportional way via:
Which can be solved for the final volume, V2, as shown below:
Thus, by plugging in the given data, we obtain:
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B. Both mechanical and chemical waethering
There are three valence electrons in an atom of Aluminum (Al).
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Al · or : Al : ·
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The answer is B.
