Answer:
1.The metalloids; boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te), polonium (Po) and astatine (At) are the elements found along the step like line between metals and non-metals of the periodic table.
2.hydrogen
The elements generally classified as nonmetals include one element in group 1 (hydrogen);
3.element iron
The element iron is in group 8, and therefore has two or three apparent valence electrons.
2Al+6HCl⇒3H₂+2AlCl₃
<h3>Further explanation
</h3>
Equalization of chemical reaction equations can be done using variables. Steps in equalizing the reaction equation:
• 1. gives a coefficient on substances involved in the equation of reaction such as a, b, or c etc.
• 2. make an equation based on the similarity of the number of atoms where the number of atoms = coefficient × index between reactant and product
• 3. Select the coefficient of the substance with the most complex chemical formula equal to 1
Reaction
Al+HCl⇒H₂+AlCl₃
aAl+bHCl⇒cH₂+AlCl₃
Al, left=a, right=1⇒a=1
Cl, left=b, right=3⇒b=3
H, left=b, right=2c⇒b=2c⇒3=2c⇒c=3/2
the equation becomes :
Al+3HCl⇒3/2H₂+AlCl₃ x2
2Al+6HCl⇒3H₂+2AlCl₃
4 sig fig in that expression
An electromagnet is a device in which, by electric current, the magnetic field is produced. Increase the number of coils and increase the strength of the current, thus, increasing the strength of an electromagnet.
The correct option is B.
<h3>What is an electromagnet?</h3>
An electromagnet is a device that consists of a magnetic core encircled by a coil, through which an electric current is carried to magnetize the core.
Wherever controllable magnets are required, such as in devices where the magnetic flux must be adjusted, reversed, or switched on and off, an electromagnet is utilized.
Thus, the correct option is B, increasing the number of coils and increasing the strength of the current.
Learn more about electromagnet, here:
brainly.com/question/13803241
Answer:
<u>structural arrangements</u>
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<h2>properties of daimond: </h2><h3>appearance: transparent</h3><h3>hardness: very hard</h3><h3>thermal conductivity :very poor</h3><h3>electric conductivity: poor</h3><h3>density:</h3>
<h3>uses: jewellery and drilling</h3>
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<h2>properties of graphite:</h2>
<h3>appearance: black shiny</h3><h3>hardness: soft ,slippery to touch</h3><h3>thermal conductivity : moderate</h3><h3>electric conductivity: good</h3><h3>density:</h3>
<h3>uses:dry cell, electric arc, pencil lead, lubricant</h3>
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<h2>How Diamond and Graphite are chemically identical?</h2>
- On heating diamond or graphite in the air, they burn completely to form carbon dioxide.
- - Equal quantities of diamond and graphite when burned, produce exactly the same amount of carbon dioxide.
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<h2>Why the physical properties of diamond and graphite are so different?</h2>
Due to the difference in the arrangement of carbon atoms in diamond and graphite
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<em><u>hope</u></em><em><u> it</u></em><em><u> helps</u></em><em><u> you</u></em><em><u><</u></em><em><u>3</u></em></h2>
