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3 years ago

How many valence electrons are in an atom of strontium (Sr)? Consult the periodic table. A. 5 B. 2 C. 47.90 D. 22

Chemistry

2 answers:

Eduardwww [97]3 years ago

6 0

<h2>Answer:</h2>

The option B is correct.

Strontium has 2 valence electrons.

<h3>Explanation:</h3>

Since strontium (Sr) is in Group 2 it will have 2 valence electrons.

Kaylis [27]3 years ago

5 0

The smallest and the basic particle of a chemical element is said to be an atom. It is made up of three subatomic particles that is electrons, protons and neutrons. The neutrons and protons are present in the nucleus of an atom whereas electrons are present in the orbits around the nucleus of the atom. There are several shells in the orbital depending on the atomic number. The electrons which are present in the outermost shell are said to be valence electrons.

They can be determined by the electronic configuration of the element.

The atomic number of strontium, $Sr$ is 38. The electronic configuration of strontium, $Sr$ is:

$1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^{10}4p^{6}5s^{2}$

From the electronic configuration it is clear that the outermost shell of strontium, $Sr$ is $5s$ . So, the number of valence electrons in strontium, $Sr$ is 2.

Hence, there are 2 valence electrons in an atom of strontium ( $Sr$ ).

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What will happen to the final pressure of a cylinder when the volume is doubled.

OLEGan [10]

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3 years ago

Two samples of the same compound are compared. what does the data represent? sample 1: 24.22 g carbon and 32.00 g oxygen sample

goblinko [34]

According to law of definite proportion:

In a compound, elements are always arranged in fixed ratio by mass.

Here, sample 1 has 23.22 g Carbon and 32.00 g Oxygen.

Converting mass into number of moles:

Molar mass of carbon is 12 g/mol and that of oxygen is 16 g/mol thus,

$n_{C}=\frac{m_{C}}{M_{C}}=\frac{24.22 g}{12 g/mol}\approx 2 mol$

Similarly, number of moles of oxygen will be:

$n_{O}=\frac{m_{O}}{M_{O}}=\frac{32 g}{16 g/mol}=2 mol$

The ratio of number of moles of carbon and oxygen will be:

$C:O=n_{C}:n_{O}=2:2=1:1$

Therefore, formula of compound will be CO.

Sample 2:

It has 36.22 g Carbon and 48.00 g Oxygen.

Converting mass into number of moles:

Molar mass of carbon is 12 g/mol and that of oxygen is 16 g/mol thus,

$n_{C}=\frac{m_{C}}{M_{C}}=\frac{36.22 g}{12 g/mol}\approx 3 mol$

Similarly, number of moles of oxygen will be:

$n_{O}=\frac{m_{O}}{M_{O}}=\frac{48 g}{16 g/mol}=3 mol$

The ratio of number of moles of carbon and oxygen will be:

$C:O=n_{C}:n_{O}=3:3=1:1$

The formula of compound will be CO.

Therefore, it is proved that carbon and oxygen are present in fixed ratios in both the samples.

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3 years ago

The Development and Characterization of Carbon Nanofiber/Polylactic Acid Filament for Additively Manufactured Piezoresistive Sen

horrorfan [7]

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<h3>what are the development and characterization of Carbon Nanofiber for Additively Manufactured Piezo resistive Sensors?</h3>

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Carbon nanofiber/polylactic acid filament for fused filament fabrication (FFF) and additive manufacturing (AM) strain sensors was studied for the effects of production factors.
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To know more about Carbon nanofiber/polylactic acid check here:brainly.com/question/15913091

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1 year ago

Symbol for protons, neutrons, electrons in chemistry.

CaHeK987 [17]

This is the symbols for protons, neutrons, and electrons

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3 years ago

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Finger [1]

Aluminum
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2 years ago

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