<span>a. x and y are atoms of the same element.
If both atoms contain the same amount of protons, they are always the same element.
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Answer:
Fluoride is commonly used in dentistry to strengthen enamel, which is the outer layer of your teeth. Fluoride helps to prevent cavities. It’s also added in small amounts to public water supplies in the United States and in many other countries. This process is called water fluoridation.
Explanation:
The statement is true. The octet rule refers to the general rule of thumb wherein atoms of main-group elements tend to bond with other atoms in such a way that each atom possesses eight electrons (octet) in their valence shell. They tend to form the same electronic configuration as the noble gases. However, there are some exceptions to this rule. One of which is silane, SiH₄. A hydrogen atom only has 1 valence electron and needs another electron to complete its energy level. This is unlike other atoms, for example, carbon which has 4 valence electrons and needs to form 4 covalent bonds to fill its energy levels. Thus, 4 hydrogen atoms need only 4 more electrons. This is given by the silicon atom which has 4 valence electrons. Therefore, when a silicon atom is bonded to 4 hydrogen atoms, the resulting molecule, SiH₄, is a stable one.
iii. True. The existence of a vacancy in a crystal decreases the energy of the material.
One of the scientific disciplines called crystallography examines how the atoms in a solid crystal are arranged. When molecules are linked together in a regular way, these crystals are created.
The mechanical, physical, and optical properties of a material can alter when crystal flaws are present. The strength of the material can be impacted by a flaw.
An irregularity in the atoms' regular geometrical arrangement within a crystalline material is referred to as a crystal defect. These flaws are caused by the solid being deformed, cooling quickly from a high temperature, or being exposed to high-energy radiation (such as X-rays or neutrons). because the vacancy cause defects and the crystal structure is disturbed this causes a decrease in energy.
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Answer:
the answer is fe20 Hope this helps!
Explanation:
