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2 years ago

17) The elements sodium, magnesium,and silicon

Chemistry

2 answers:

irakobra [83]2 years ago

8 0

A period is a horizontal row and therefore these elements are all in the same period.

If you pull up an image of the periodic table, you will see that all of them are in the same row.

They are not isotopes of each other because an isotope is the same element with a different number of neutrons (example: carbon-12, carbon-13).

Hopefully I helped :)

Murljashka [212]2 years ago

7 0

Answer:

B) are in the same period of elements.

Explanation:

The elements sodium, magnesium, and silicon

A) are isotopes of each other . NO. Isotopes are 2 or more forms of the same element, with a different number of neutrons.

B) are in the same period of elements. YES.

Let's consider the electron configuration of these elements.

₁₁Na 1s² 2s² 2p⁶ 3s¹

₁₂Mg 1s² 2s² 2p⁶ 3s²

₁₄Si 1s² 2s² 2p⁶ 3s² 3p²

Since the valence electrons are in the level 3, they all belong to the third period in the periodic table.

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4 moles of hydrogen react with 5 moles of oxygen to form water, identify the excess reagent?

Fynjy0 [20]

Answer:

Excess Reagent = oxygen

Explanation:

Limiting reagent: The substance that is totally consumed when the reaction is completed.

Excess reagent: The substance left after the limiting reagent is consumed completely

The balanced chemical equation for formation of water is as follow:

$2H_{2}+O_{2}\rightarrow 2H_{2}O$

This means when 2 moles of hydrogen reacts with 1 mole of oxygen, 2 moles of water is produced.

Hence the ratio in which hydrogen and oxygen gas reacts is 2:1

Now if 2 mole hydrogen require 1 mole of oxygen ,then 4 mole hydrogen need 2 mole of oxygen.

$H_{2}:O_{2}=2:1$

$H_{2}:O_{2}=4:2$

Here 5 mole of oxygen is reacting but only 2 mole is required .

Oxygen is in excess.

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3 years ago

In Niels Bhor's model of the atom, electrons move

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3 years ago

How many moles of hcl are produced from a reaction with 6.2 moles of h2 given the following equation

Bas_tet [7]

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3 years ago

To a 25.00 mL volumetric flask, a lab technician adds a 0.150 g sample of a weak monoprotic acid, HA , and dilutes to the mark w

Elis [28]

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