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Chemical Formula don't have a plus (+) sign in them. What you have shown us

is a reaction

 

This forms HCL(aq)' date=' the [i']formula[/i] of hydrochloric acid

 

Is that clear?

But, if hydrochloric acid react with something else , what should the formula of the raw material ( hydrochloric acid , HCI or HCI+H2O?)???

Why light converges or diverges when they passes the centre plane of the lens(middle of lens)??

When we draw graphs,

we redirect the rays when they exactly passes at the middle.

When we write chemical formula, such as

water+sodium hydroxide

H2O+NaOH, if we don't know the product , can we still

have the correct answer?

Why do chemists name HCI(aq) the formula as hydrochloric acid,

but not name it as H2O+HCI = hydrochloric acid????

it`s Part of a plant cell yes' date=' but they are not cells themselves

 

and you don`t have to call any of us "Sir" [/quote']

 

Hi YT, how about the liver? Some books said it consists of cells.

 

----------------difficult...

Is chloroplast considered as cell?

Generally, polyatomic ions contain polar covalent bonds. Still, the difference between polar covalent and ionic bonding is really subject to opinion. The "rule" chemists use is that if the electronegativity difference of the bonded atoms is greater than or equal to 1.7, it's an ionic bond.

1.7?? How about H2F? The electronegativity of hydrogen atom is 1.0 while the electronegativity of fluorine atom is 4.0, then why we still look it as a covalent compound?

In my experiment , The plant (Chlorophyll )absorbs blue lights the highest but absorbs green light the lowest, what's the reason?

Do the reasons are 1. the reflection of light ( colour ) ,2.the high energy from the blue light ?

Would you like to suggest some other possible reasons for me, thank you.

My teacher asked my class to do a homework to find the properties of hydrogen.

I want to know that why once hydrogen atoms combines with other non-metal atoms, it shares its electrons instead of losing it?

when it forms bonds, it is essentially gaining or losing electrons. when it bonds with metals, it "gains" e- (ex. Na3N). when it bonds with most nonmetals, it loses e- (ex. NO2).

But, does the bond of the NO3 is ionic bond?

And also, why in H2O molecule, it is bonded with covalent bond but not ionic bond, doesn't that hydrogen atoms lose electron for oxygen

because of the strong electrostatic force of attraction from the strong nucleus of oxygen.

What provided for the condition?

Thank you. Anyway, is it true that carbonic acid dissolve in the chloroplast?

you mentioned "nitrite" (NO2-) but actually said nitrate (NO3-).

 

in the nitrite ion' date=' N takes a +3 charge, while each O takes a -2 charge. since there are 2 O trying to make 2 bonds each (in order to take the -2 charge), the N cannot give up enough e-. as a result, the one of the O atoms forms a coordinate covalent bond with the N and takes a negative charge.

 

the same thing works with the nitrate ion, except the N takes a +5 charge and collectively, the O wants to take a total of -6 worth of charges and can't. so, once again, one of the O takes a -1 charge and forms a coordinate covalent bond.[/quote']

 

Sorry, I made a mistake. Actually, when I was writing it, I first thought nitrite

and wrote. Then I found it could be calculated, so I write the formula of that polyatomic ion nitrate ion.

By the way, would you tell me something I am still confused with?

How do you know that when nitrogen atom wants to gain 3 electrons and when to lose 5 electrons to become duplet state(the same electronic arrangement of helium atom) while it combines with other atoms?

I hope you would answer me. DEAR

My internet explorer 6.0 has problem.

I want to reinstall it, but I don't know the steps.

Please teach me

Generally' date=' polyatomic ions contain polar covalent bonds. Still, the difference between polar covalent and ionic bonding is really subject to opinion. The "rule" chemists use is that if the electronegativity difference of the bonded atoms is greater than or equal to 1.7, it's an ionic bond.

 

NH4+ is an actual compound because it forms three covalent bonds and a fourth bond called a coordinate covalent bond. This fourth bond is formed because the H provides both electrons required for the bond.

 

Polyatomic ions don't have 0 charges because they contain ions.

Ex:

Sulfate (SO4) with a -2 charge.

O

O=S=O

O

 

The sulfur can only make 6 bonds. The O2 each want to make 4 bonds, but cant, since sulfur cannot form 8 bonds. As a result, 2 oxygen atoms make double bonds and thus are happy, so to speak, while the other 2 oxygen atoms can only make 1 bond each. They are not happy. The SO4 -2 ion is unstable, as are all polyatomic ions. This is why you will never see a polyatomic ion alone unless suspended in an aqueous solution.

 

To estimate the charge, just figure out the amount of bonds the central atom (like N in NH4+ and S in SO4-2) can make and how many bonds the outside atoms would like to make. Then figure out the difference and there's your charge. Another example is the borate ion. Boron wants to make 3 bonds. There are 3 oxygen bonded to it, all of which want to make 2 bonds. The boron can bond with them all, but cannot form even one double bond (let alone 3) and still have all 3 oxygen atoms bonded to it. Consequentially, you end up with the following molecule:

O

O-B-O

 

Each O has a -1 charge since it only has 1 bond. There are 3 oxygen atoms. Therefore, borate is a -3 charged polyatomic ion.

 

 

I hope I answered all your questions well.[/quote']

 

 

1.How about nitrite(NO3-), why does the charge is like this but not 3-?

2.make 3 bond=to have 3 more electrons?

How does a sea is covered with ice?

Isn't that warmer water flows upward and cold water sink?

How does a car convert diesel or petrol into energy?

I think it does not use the thermal turbine, does it ?

Thank you. Your explanation helps me a lot.

However, I have still a question.

Would you like to answer me?

Is Covalent compound is compound?

Is ion a compound or element?

If ion is a not a compound, then why is polyatomic ion a covalent compound?

Cation combines with anion to form ionic compound,right?

Actually, maybe I don't have the clear concept about ionic compound and convalent compound?

I am actually a questional boy..

Everthing can reflect.

And we can see our face when a glass in front of us.

Then, is that is internal reflection only, and does not have the reflection like mirror?

Einstein had a question when he was 14.

That question was "When I fly (in vacuum and without gravity) towards in space with light speed (30km/s), then I take my mirror in front of me, will I see my mirror((in terms of physical words, his face emits light and strike the mirror and then back into his eye))?"

After some periods of time, he got the answer, that is yes.

Until now , I still don't know why it is possible.

Relativity stated that nothing is faster than light, then what makes the lights from his face are fast enough to reach the mirror moving with light speed?

I beg experts can help me solve it.

Thank you, now I recognised that stems have chlorophyll.

Would anyone help solve my questions?

1.Are all polyatomic ions have covalent bonds(the electrostatic forces between the shared electrons and bonded atoms)?

2.Are they covalent compound?

3.Like ammonium(NH4), how does it exist?

4.Why aren't they have 0 charged?

5.How to estimate the charge of them?

Is that true only leaves have chlorophyll?

Do stems or other animals have c lorophyll?

Thank you very much.

May I ask other questions?

Does light reaction and dark reaction occur in the same position of an chloroplast?

How does the oxygen molecule leave the leave after the light-dependent stage?

Is that true "only leaves have chlorophyll."?

I hope experts would like to help me to solve my brain questions.

the excess wont dissolve and will remain as a mixture

 

very High pressures of CO2 can make it a solid' date=' as can very low temperatures [/quote']

 

Thank Thank.Your explanation make me learn a lot. May I ask about what is the excess thing, is it carbon dioxide or water?

Thanks. By the way, I want to ask how carbon dioxide becomes liquid?

And does soda water is a mixture or compound?