Answer:
Option D
Explanation:
Rutherford deduced that the atomic nucleus was positively charged because the alpha particles that he fired at the metal foils were positively charged, and like charges repel. Alpha particles consist of two protons and two neutrons, so they are positively charged. In Rutherford's experiments most of the alpha particles passed straight through the foil without being deflected. However, occasionally the alpha particles were deflected in their paths, and rarely the alpha particles were deflected backward at a 180 degree angle.
Since like charges repel, Rutherford concluded that the cause of the deflections of the positively charged alpha particles had to be something within the atom that was also positively charged. Rutherford concluded from his metal foil experiments that most of an atom is empty space with a tiny, dense, positively charged nucleus at the center that contains most of the mass of the atom.
Seven valence electrons are present in the 'Lewis structure' for the given chlorine atom
A Chlorine atom has total 17 electrons in total. In the 'first orbit' 2 electrons, 10 electrons in the 'second orbit' and finally 7 electrons in the last orbit. As Chlorine is a Group 7 element, chlorine will have 7 'valence electrons' in its outermost orbit. While drawing the 'Lewis structure' of Chlorine we shall put seven dots that is the electrons or valance electrons around the symbol of Chlorine (CI).
<h3>
What are Valence electrons ?</h3>
The electrons in an atom's outermost shell, or energy level, are called valence electrons. For instance, the valence electrons of oxygen are six, with two in the 2s subshell and four in the 2p subshell.
- An atom's outer shell electrons, known as valence electrons, can take role in the creation of chemical bonds. When two atoms establish a single covalent bond, normally both atoms contribute one valence electron to create a shared pair. The ground state of an atom is its state with the least amount of energy.
Learn more about Valence electron here:
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Answer:
3.1% is the fraction of the sample after 28650 years
Explanation:
The isotope decay follows the equation:
Ln[A] = -kt + Ln[A]₀
<em>Where [A] could be taken as fraction of isotope after time t, k is decay constant and [A]₀ is initial fraction of the isotope = 1</em>
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k could be obtained from Half-Life as follows:
K = Ln 2 / Half-life
K = ln 2 / 5730 years
K = 1.2097x10⁻⁴ years⁻¹
Replacing in isotope decay equation:
Ln[A] = -1.2097x10⁻⁴ years⁻¹*28650 years + Ln[1]
Ln[A] = -3.4657
[A] = 0.0313 =
<h3>3.1% is the fraction of the sample after 28650 years</h3>
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If I remember correctly, the answer is <span>Friction force.</span>
