Answer:
Barium has the same number of valence electrons as calcium
Explanation:
Valence electrons is the number of electrons of an atom on the outer shell.
Those valence electrons can participate in the formation of a chemical bond (if the outer shell is not closed); in a single covalent bond, both atoms in the bond contribute one valence electron in order to form a shared pair.
<u>Calcium</u> is an atom, part of group 2, called the alkaline earth metals. The alkaline earth metals have 2 valence electrons.
<u>Sulfur </u>is part of a group 16, called the chalcogens or oxygen family. Those atoms have 6 valence electrons. They can form a bound with atoms of group 2 such as calcium, but do not have the same number of valence electrons.
<u>Potassium</u> is part of group 1, called the alkali metals or lithium family. Those atoms have 1 valence electrons. That means Potassium do not have the same number of valence electrons like calcium.
<u>Neon</u> is part of group 18, the noble gasses. Those are stable atoms, which means they have 8 valence electrons. They do not have the same number of valence electrons like Calcium.
<u>Barium</u> an atom, part of group 2, called the alkaline earth metals. The alkaline earth metals have 2 valence electrons. Calcium is also part of this group.
This means barium has the same number of valence electrons as Calcium.
Fluorite is harder than gypsum but softer than apatite. Thus, the correct option is B.
<h3>What is the hardness of any element?</h3>
The hardness of any element may be defined as the capability of a material to oppose the process of deformation and remains in actual shape precisely.
According to the table of hardness scales by Mohs, the increasing order of given hardness of given elements is as follows:
Gypsum < Fluorite < Apatite.
Therefore, Fluorite is harder than gypsum but softer than apatite. Thus, the correct option is B.
To learn more about the Hardness of elements, refer to the link:
brainly.com/question/23721736
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Answer:
They are strong intermolecular forces
Explanation:
Covalent forces are very strong intermolecular forces. In fact, we can say they are the strongest. This is because several big and giant molecules have covalent bonds holding their molecules together. A good example of this is the buckministerfullerence molecule which contains carbon atom to the order of 60 carbon atoms. It is a very giant molecule and it is covalent bond that is holding the molecules together
The strongest substance in the world is diamond. It is so strong that no other substance can cut it asides another diamond. As strong as it is, the molecule is held together by very strong intermolecular forces of covalent bonds which confers the strength it has on it
If this is a true of false question, note that it's false. Unsaturating the color, meaning giving it a lower amount up to zero, can cause gray tones - especially when it comes to pictures when editing it. High color saturation can make the color tone very vivid.
