Questions tagged [covalent-compounds]

For questions about covalent compounds - which are compounds in which all intermolecular bonds between atoms are considered mostly covalent - have a stronger covalent than ionic or metallic component. This tag is not to be confused with [bond].

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46
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5answers
12k views

Fundamental forces behind covalent bonding

I understand that covalent bonding is an equilibrium state between attractive and repulsive forces, but which one of fundamental forces actually causes atoms to attract each other? Also, am I right ...
24
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5answers
39k views

Bonding in the phosphate ion

I'm looking for an explanation of the bonding in the phosphate (PO43−) ion: (Image courtesy of Wikipedia) Phosphorus (15P) - being the fifteenth element - has fifteen electrons, five valence ...
78
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4answers
38k views

Bonding in diatomic C2, a carbon-carbon quadruple bond?

Carbon is well known to form single, double, and triple $\ce{C-C}$ bonds in compounds. There is a recent report (2012) that carbon forms a quadruple bond in diatomic carbon, $\ce{C2}$. The excerpt ...
16
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5answers
26k views

Metal Compounds that bond covalently [closed]

I would like to ask if anyone has a list or knows which covalent compounds have metals in them. For example, beryllium and aluminium are both metals but they bond covalently with chlorine to form ...
39
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1answer
11k views

Can 100% covalent bonds exist?

Every covalent bond has some ionic character and every ionic bond some covalent character. I can understand why a completely ionic bond is an ideal situation. But completely covalent bonds can exist(?)...
11
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1answer
5k views

Does sulfur and phosphorus expand their octet?

There are many compounds in which the stability of a molecule is not governed by the presence of octet configuration in central atom. In most of the cases the central atom is generally sulfur or ...
15
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1answer
1k views

Why do different elements form different types of carbides?

What property of the elements make them form different types of carbides like: $\ce{Be}$ and $\ce{Al}$ - $\ce{Be2C}$ and $\ce{Al4C3}$ (Methanides) contains $\ce{C^4-}$ ion $\ce{Na}$ and $\ce{Ca}$ - $...
7
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3answers
8k views

Does the shared electron in Covalent bonds revolve around nucleus?

We know that electrons are charges that revolve around the nucleus. Then, when in covalent bonds the electron is shared; does the electron obey the rule?
9
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3answers
11k views

Is KHF2 an ionic compound or a covalent compound?

The statement below is an excerpt from my school textbook:- Because of the tendency of fluorine to form hydrogen bond, metal fluorides are solvated by $\ce{HF}$ giving species of the type $\ce{...
14
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3answers
19k views

How does chlorine form more than 1 bond?

How are perchlorate or chlorate or chlorite ions and their respective acids or compounds formed. $\ce{Cl}$ can't form more than one bond but still... $\rightarrow$'Perchlorate ion' $\rightarrow$'...
12
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2answers
6k views

Which has the largest bond angle between water, oxygen difluoride and dichlorine oxide?

Which one out of $\ce{H2O}, \ce{Cl2O}, \&\ \ce{F2O}$ will have largest bond angle? I think it should be $\ce{H2O}$ because oxygen is most electronegative in this case so electrons will be more ...
11
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2answers
3k views

Oxygen and sulfur bonding

Why does oxygen form a double bond in $\ce{O2}$ but sulfur, also from group 16, forms single bonds in $\ce{S8}$?
4
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1answer
673 views

Does boron form compounds without covalent bonds?

I have read that boron, due to the very high sum of its first three ionization energies, it is not able to form its +3 ions, and thus it generally forms only covalent compounds. But in a popular ...
36
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7answers
119k views

Are metallic/ionic bonds weaker than covalent bonds?

In mineralogy class, I was taught that metallic and ionic bonds are weaker than covalent bonds and that's why quartz and diamond have such a high hardness value. However, in organic chemistry class, I ...
10
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4answers
115k views

Is melting/boiling point of ionically bonded substance higher than of covalently bound?

Is the melting and boiling point of ionic bond usually higher than covalent bond? I know that compounds with ionic bonds are usually solid at room temperature, so I want other answers than this. (...
7
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3answers
25k views

Why the bond angle of PH3 is lesser that that of PF3?

We can explain why the bond angle of $\ce{NF3}$ (102°29') is lesser than $\ce{NH3}$ (107°48') by the VSEPR theory, since lone pair lone pair repulsion is greater than lone pair bond pair repulsion. ...
7
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1answer
41k views

How to know it when I see a covalent network?

This is a well-known (better said: well-discussed) question in the internet. When you look for answers for popular questions, you usually see them with a variable degree of reliability and complexity. ...
17
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3answers
23k views

Why do Magnesium and Lithium form *covalent* organometallic compounds?

Lithium and magnesium are Group 1 and Group 2 elements respectively. Elements of these groups are highly ionic, and I've never heard of them forming significantly covalent inorganic compounds. Yet ...
7
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1answer
16k views

Is the bond in HF ionic while it is covalent in HCl?

Why would a hydrogen atom "donate" to fluorine in an ionic bond but not in $\ce{HCl}$? Why would $\ce{H}$ and chlorine share instead of $\ce{Cl}$ just stripping it away like $\ce{F}$ does?
13
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2answers
11k views

Is pyrite (FeS₂) an ionic or a covalent compound?

I have searched all over the web and found a lot of diverse explanations, but none of them are concluding exactly whether $\ce{FeS2}$ (solid - pyrite) is a covalent or an ionic compound. From ...
23
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2answers
1k views

Why are silicon analogs of alkenes or alkynes so difficult to make?

We know that there are silicon analogs of alkanes, but according to Wikipedia, silicon analogs of alkenes or alkynes are virtually unknown. How come?
15
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2answers
5k views

Why are noble metals more electronegative then most metals?

I was researching about electronegativity when I looked up what a graph of electronegativity within the periodic table is. And, this appeared. I scanned it, matching up everything I knew about the ...
5
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1answer
9k views

Sulfur trioxide - vacant d-orbitals

Sulfur trioxide violates the octet rule. Upon drawing the Lewis dot structure for sulfur trioxide, we see that the central sulfur atom is bonded to three other oxygen atoms by double covalent bonds. ...
1
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1answer
706 views

Hypervalency in elements in the second period

In my experience, most texts that address hypervalency say that it only occurs from elements in the 3rd period and onwards. This explains the occurrence of $\ce{Cl2O7}$ or chlorine heptoxide. However, ...
4
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3answers
1k views

Why is PbCl₄ covalent?

My answer: The inert pair effect in $\ce{Pb}$ causes it to pull back the electrons, resulting in polarisation. My teacher's answer: An ionisation state of $+4$ is too difficult to achieve, and it is ...
8
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2answers
11k views

Is this a valid structure for the nitrate ion?

Why is the below structure not considered a valid structure for the nitrate ion? Is it because adding a double bond reduces the formal charges present on the nitrogen? Does the above form exist ...
2
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1answer
3k views

How would one compare the magnitude of covalent character between SnCl4 and SnF2 using Fajan's Rules?

It is easy to compare two ionic compounds when one of the ions is same. However, how do we compare two compounds if one of the ions is the same element but just has different charge and the other ion ...
0
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1answer
365 views

Are bulkier molecules more likely to react? [closed]

I have heard a theory from someone and just wanted to confirm if its true or not. Is it true that more bulkier an organic compound is, more likely it is to react? So does this mean that higher the ...
33
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3answers
34k views

Why is the bond length of CO+ less than that of CO?

According to molecular orbital theory, the bond order of $\ce{CO}$ is 3. When $\ce{CO+}$ is formed, the bond order decreases to 2.5, and thus the bond length should increase. However, the bond length ...
19
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3answers
10k views

Why are pi bonds only formed when sigma bonds are formed?

While studying about bonding there was one statement that "pi bonds can only be formed only with sigma bonds" as we know that in double bond there is 1 sigma bond and 1 pi bond but then one question ...
22
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2answers
10k views

Why do XeO and XeF8 not exist?

Since Neil Bartlett's 1962 discovery that xenon was capable of forming chemical compounds, a large number of xenon compounds have been discovered and described. Almost all known xenon compounds ...
8
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4answers
4k views

Why does stannous chloride occur despite the octet rule?

Shouldn't reaching an octet be any atom's "goal"? However, I've recently learned about cases that are either expanding octets, or have lesser than "enough" electrons for an octet abiding. e.g.: S in ...
14
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2answers
8k views

Does fluorine in FNO3 have +1 oxidation number?

According to my textbook and also Wikipedia, fluorine nitrate is a compound which can be created (though it is unstable). Also my textbook says that fluorine has a $+1$ oxidation state. But how is $+1$...
9
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2answers
45k views

Are ionic bonds stronger than covalent bonds?

A covalent bond involves overlapping of orbitals while an Ionic bond involves charge separation. Why are bonds formed by the overlapping of orbitals weaker than charge separation; why is an ionic ...
3
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4answers
97k views

Percentage ionic character when electronegativity is given

What is the ionic character of a bond, $\ce{A-B}$, in terms of the electronegativities of $\ce{A}$ and $\ce{B}$ ($\chi_\ce{A}$ and $\chi_\ce{B}$)? I have been taught that the percentage ionic ...
6
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2answers
16k views

Is beryllium difluoride covalent or ionic?

My textbook says that despite the large electronegativity difference $\ce{BeF2}$ is covalent since the beryllium ion will have too much charge density and it will attract the fluorine electron cloud ...
6
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1answer
12k views

Does water ionically bond to chloride ion?

This user absolutely insists that when a chloride ion is present in water (for example, when $\ce{NaCl}$ dissolves in water) that $\ce{Cl-}$ ion is ionically bound to the hydrogen atom: https://...
4
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2answers
3k views

Is there a word for a compound that has both ionic and covalent bonds?

For example, calcium carbide (CaC$_2$) has covalent C‒C bonds and ionic Ca$^{2+}$‒ C$_2^{2-}$ bonds.
3
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1answer
1k views

How to rationalise the increasing bond length order in the carbonate ion, carbon monoxide, and carbon dioxide?

I am unable to rationalise the order of increasing bond length in $\ce{CO3^2-}$, $\ce{CO}$ and $\ce{CO2}$. Having gone through the factors affecting bond length in two different books, my approach to ...
10
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1answer
12k views

What is melting? Which bonds do we break to melt something?

To melt diamond, we have to break the covalent bonds, which we can consider 'intermolecular' because it is one giant molecule. To melt Methane, we have to break the van der Waals (intermolecular) ...
9
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3answers
7k views

Effect of noble gas configuration on polarising power

I don't understand this statement written in my textbook about the polarising power of cations: If two cations have the same size and charge, then the one with pseudo noble gas configuration ( with ...
6
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2answers
6k views

Relative O-O bond lengths in O2X2 molecules (X = H, F, Cl)

I am facing problem in the following question: What is the order of bond length of $\ce{O-O}$ in the following compounds: $\ce{H2O2, O2F2, O2Cl2}$ In my view since fluorine is more ...
12
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3answers
1k views

Do Li4 or Li8 molecules exist?

I've read that alkali metals form ionic bonds; $\ce{Li}$ is an exception which majorly forms covalent bonds. Wikipedia says dilithium exists. This makes me wonder why $\ce{Li_8}$ doesn't exist. It ...
1
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2answers
9k views

Partial charges in a covalent bond

My professor stated the following statement: In a covalent bond, there is a presence of a partial charge in the atoms that combine to form a compound. For example in $\ce{H2O}$, since $\ce{O}$ is ...
12
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1answer
32k views

Why can't carbon form an ionic bond?

My textbook says that a $\ce{C^{4+}}$ cation cannot be formed because it requires a lot of energy to remove 4 electrons. Formation of ionic bonds involve "removing" electrons and there seems to be ...
10
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1answer
715 views

Stable natural helium hydride?

Reading the transcript of the Royal Society of Chemistry podcast Helium Hydride, they state that helium hydride is possibly the most ancient compound to form in the Universe. They make the assertion ...
8
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3answers
16k views

The Crisscross method for finding the chemical formula

I am reading this wikipedia article that I don't understand. What I don't understand is: suppose we have two elements $X$ and $Y$ having oxidation numbers $x$ and $y$ respectively. Can we prove ...
7
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2answers
30k views

How many hydrogen bonds in these compounds?

We usually get some questions about how many hydrogen bonds these compounds can create, we use it to differentiate between the boiling point of each one of them so it would be great if you could help ...
7
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2answers
370 views

Do allenes form rings?

I was wondering whether allenes can form rings; geometrically speaking, this seems like it would be energetically unfavorable due to their 180 degree linear geometry.
6
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2answers
4k views

Is there any way of representing a dative/coordinate covalent bond?

I was wondering if there was any way of representing a dative/coordinate covalent bond on a chemical diagram. A single bond can easily be represented as a single line, a double bond as a double line ...