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Brums [2.3K]
3 years ago
9

What is the period number in which helium is found

Chemistry
2 answers:
julsineya [31]3 years ago
6 0

Answer:

Helium is the second element on the periodic table. It is located in period 1 and group 18 or 8A on the righthand side of the table. This group contains the noble gases, which are the most chemically inert elements on the periodic table. Each He atom has two protons and usually two neutrons and two electrons.

Explanation:

thoughtco.com

GaryK [48]3 years ago
5 0

Answer:

period 1 and group 18 or 8A on the righthand side of the table.

Explanation:

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An element or compound which occurs naturally in the earth is a mineral
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The solubility of acetanilide in hot water (5.5 g/100 ml at 100∘C) is not very great, and its solubility in cold water (0.53 g/
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89.4%

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Given that you have 14.5 moles of n2, how many moles of h2 are theoretically needed to produce 30.0 moles of nh3 according to re
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45 moles of H₂ are theoretically needed to produce 30.0 moles of NH₃

<h3>Further explanation</h3>

Stoichiometry in Chemistry learn about chemicals mainly emphasizes quantitative, such as the calculation of volume, mass, number, which is related to numbers, molecules, elements, etc.

A reaction coefficient is a number in the chemical formula of a substance involved in the reaction equation. The reaction coefficient is useful for equalizing reagents and products.

In the reaction there are also manifestations of reagent substances namely gas (g), liquid (liquid / l), solid (solid / s) and solution (aqueous / aq).

The concentration of a substance can be expressed in several quantities such as moles, percent (%) weight/volume,), molarity, molality, parts per million (ppm) or mole fraction. The concentration shows the amount of solute in a unit of the amount of solvent.

  • Mole

The mole itself is the number of particles contained in a substance amounting to 6.02.10²³

Mole can also be sought if the amount of substance mass and its molar mass is known

\large{\boxed{\boxed{\bold{mol=\frac{mass}{molar\:mass}}}}

 

Reaction that happens :

N₂ +3H₂ ⇒ 2NH₃

mole N₂ : H₂ : NH₃ = 1 : 3 : 2

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mole~H_2~=~\frac{3}{2}\times~30~mole

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mole~NH_3~=~\frac{2}{1}~\times~14.5

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<h3>Learn more </h3>

The mass of one mole of raindrops

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moles of water you can produce

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Keywords: mole,  NH₃, N₂, H₂

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