____________ was the first chemist to organize elements by atomic number

There are several aromatic compounds with the formula C8H9Cl. Draw those that have a trisubstituted ring where the methyl groups

Kryger [21]

Answer:

$3-Chloro-1,2-dimethylbenzene$

$4-Chloro-1,2-dimethylbenzene$

Explanation:

Such types of compounds in which conjugated planer ring system and delocalized pi electrons are present are called aromatic compounds such as Toluene, Benzene and some other. Generally, these compounds follow Huckle's rule. The trisubstituted ring means a compound in which three hydrogen atoms are replaced by three other groups. In the given compound two hydrogen atoms are replaced by two methyl groups and one hydrogen atom is replaced by one Chlorine atom. From the given compound $3-Chloro-1,2-dimethylbenzene$ , and $4-Chloro-1,2-dimethylbenzene$ can be drawn.

7 0

3 years ago

Determine the number of protons, electrons, neutrons, valence electrons and valency in Oxygen atom (O) and Oxide ion (O2-). Comp

wolverine [178]

Answer:

Atom (O) Ion (O²⁻)

Protons 8 8

Electrons 8 10

Neutrons 8 8 ← only for the oxygen-16 isotope.

* The number of neutrons depends on the specific isotope. It is equal to the mass number of the isotope less the number of protons.

Explanation:

Oxygen is the element with atomic number 8. That means that the oxygen atoms have 8 protons.

Protons have relative positive charge equal to +1 and electrons have relative negative charge -1: same magnitude opposite sign.

Thus, the neutral oxygen, O, has also 8 electrons and 8 protons.

As per the number neutrons it depends on the specific isotope.

The isotopes are identified by the mass number, which is the number of protons plus neutrons. For instance, oxygen-16 isotope has mass number 16, 8 protons and 8 neutrons, while oxygen-15 isotope has mass number 15, 8 protons and 7 neutrons.

Oxide ion O²⁻ is the oxygen ion with -2 charge, meaning that it has 2 more electrons than protons. Then, it has 8 protons and 10 electrons, again the number of neutrons depend of the specific isotope.

The stability of an atoms or ion refers to its trend to remain in the same state or react to form another species. The ions O²⁻ are less stable than the neutral atoms O, because the negative charge will be attracted to any positive ion so ti will react faster than the neutral oxygen atom (O).

8 0

3 years ago

1. Stirring increases the rate of solution

Blababa [14]

Answer:

1) The correct answer is A. Collision

2) A hot solvent helps a solid dissolve faster because an increase in kinetic energy that also increases the rate of collisions

Explanation:

When a solute is added into a solvent and stirred, the solute particles get distributed to all parts of the solvent as a result of stirring.

More collisions occur between the solute and the solvent due to stirring. This increases the rate of dissolving.

When a solvent is heated, then the kinetic energy would increase and the atoms will collide with a much greater force. As a result, ore solute will be able to dissolve in the solvent.

3 0

2 years ago

Can someone help me fill out the chart and explain what i should do, please?

Alina [70]

To determine the electronegativity for each bond you need to calculate the difference of electronegativity of the atoms forming the bond.

If the difference is equal or greater than 1.7 you have an ionic bond.

If the difference is between 0.4 and 1.6 you have a polar covalent bond.

If the difference is between 0 and less than 0.4 you have a nonpolar covalent bond.

1) In NH₃ there is a nitrogen - hydrogen bond.

electronegativity of nitrogen - electronegativity of hydrogen =

3 - 2.2 = 0.8 → polar covalent bond

2) In N₂ there is a nitrogen-nitrogen bond.

electronegativity of nitrogen - electronegativity of nitrogen =

3 - 3 = 0 → nonpolar covalent bond

3) In H₂O there is an oxygen - hydrogen bond.

electronegativity of oxygen - electronegativity of hydrogen =

3.5 - 2.2 = 1.3 → polar covalent bond

4) In PCl₃ there is a chlorine - phosphorus bond.

electronegativity of chlorine - electronegativity of phosphorus = 3 - 2.1 = 0.9 → polar covalent bond

4) In HBr there is a bromine - hydrogen bond.

electronegativity of bromine - electronegativity of hydrogen = 2.8 - 2.2 = 0.6 → polar covalent bond

5) In MgCl₂ there is a chlorine - magnesium bond.

electronegativity of chlorine - electronegativity of magnesium = 3 - 1.2 = 1.8 → ionic bond

6) In F₂ there is a fluorine - fluorine bond.

electronegativity of fluorine - electronegativity of fluorine =

4 - 4 = 0 → nonpolar covalent bond

7) In CO₂ there is an oxygen - carbon bond.

electronegativity of oxygen- electronegativity of carbon =

3.5 - 2.5 = 1 → polar covalent bond

8) In LiCl there is a chlorine - lithium bond.

electronegativity of chlorine - electronegativity of lithium =

3 - 1 = 2 → ionic bond

9) In Na₂O there is an oxygen - sodium bond.

electronegativity of oxygen - electronegativity of sodium =

3.5 - 0.9 = 2.6 → ionic bond

10) In CCl₄ there is a chlorine - carbon bond.

electronegativity of chlorine - electronegativity of carbon =

3 - 2.5 = 0.5 → polar covalent bond

5 0

3 years ago

Which type of reaction is represented by the generic equation ab cd right arrow. ad cb? combustion decomposition single replacem

arsen [322]

The illustration would be that of a double replacement reaction.

<h3>What are double replacement reactions?</h3>

They are reactions in which 2 ionic compounds exchange ions to form two new products.

Thus, in the reaction: ab + cd ----------> ad + cb

ab and cd are two ionic compounds. The b in ab is replaced by the d in cd while the d in cd itself is replaced by the b in ab. Hence, new products, ad and cd, are formed.

More on double replacement reactions can be found here: brainly.com/question/19267538

#SPJ4

4 0

1 year ago