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CoO ( s ) + 2HNO 3 ( a q ) Co ( NO 3 ) 2 ( a q ) + H 2 O ( l )
Sc 2 O 3 ( s ) + 6HCl ( a q ) 2ScCl 3 ( a q ) + 3H 2 O ( l )

The oxides of metals with oxidation states of 4+ are amphoteric, and most are not soluble in either acids or bases. Vanadium(V) oxide, chromium(VI) oxide, and manganese(VII) oxide are acidic. They react with solutions of hydroxides to form salts of the oxyanions VO 4 3− , CrO 4 2− , and MnO 4 . For example, the complete ionic equation for the reaction of chromium(VI) oxide with a strong base is given by:

CrO 3 ( s ) + 2Na + ( a q ) + 2OH ( a q ) 2Na + ( a q ) + CrO 4 2− ( a q ) + H 2 O ( l )

Chromium(VI) oxide and manganese(VII) oxide react with water to form the acids H 2 CrO 4 and HMnO 4 , respectively.

Hydroxides

When a soluble hydroxide is added to an aqueous solution of a salt of a transition metal of the first transition series, a gelatinous precipitate forms. For example, adding a solution of sodium hydroxide to a solution of cobalt sulfate produces a gelatinous pink or blue precipitate of cobalt(II) hydroxide. The net ionic equation is:

Co 2+ ( a q ) + 2OH ( a q ) Co ( OH ) 2 ( s )

In this and many other cases, these precipitates are hydroxides containing the transition metal ion, hydroxide ions, and water coordinated to the transition metal. In other cases, the precipitates are hydrated oxides composed of the metal ion, oxide ions, and water of hydration:

4Fe 3+ ( a q ) + 6OH ( a q ) + n H 2 O ( l ) 2 Fe 2 O 3 · ( n + 3 ) H 2 O ( s )

These substances do not contain hydroxide ions. However, both the hydroxides and the hydrated oxides react with acids to form salts and water. When precipitating a metal from solution, it is necessary to avoid an excess of hydroxide ion, as this may lead to complex ion formation as discussed later in this chapter. The precipitated metal hydroxides can be separated for further processing or for waste disposal.

Carbonates

Many of the elements of the first transition series form insoluble carbonates. It is possible to prepare these carbonates by the addition of a soluble carbonate salt to a solution of a transition metal salt. For example, nickel carbonate can be prepared from solutions of nickel nitrate and sodium carbonate according to the following net ionic equation:

Ni 2+ ( a q ) + CO 3 2− NiCO 3 ( s )

The reactions of the transition metal carbonates are similar to those of the active metal carbonates. They react with acids to form metals salts, carbon dioxide, and water. Upon heating, they decompose, forming the transition metal oxides.

Other salts

In many respects, the chemical behavior of the elements of the first transition series is very similar to that of the main group metals. In particular, the same types of reactions that are used to prepare salts of the main group metals can be used to prepare simple ionic salts of these elements.

A variety of salts can be prepared from metals that are more active than hydrogen by reaction with the corresponding acids: Scandium metal reacts with hydrobromic acid to form a solution of scandium bromide:

2Sc ( s ) + 6HBr ( a q ) 2 ScBr 3 ( a q ) + 3H 2 ( g )

The common compounds that we have just discussed can also be used to prepare salts. The reactions involved include the reactions of oxides, hydroxides, or carbonates with acids. For example:

Questions & Answers

What is chemistry
khausar Reply
scientific study of structure of substances and of the way that they react with other substances
Haider
Thanks
khausar
welcome
Haider
Hi
khausar
hi 2
Haider
whr u from
Haider
are u writing GCE
Equin
Cameroon and u
Equin
Please what nuclear fusion and nuclear fission
ALABI Reply
في التسمية الشائعة للكيتونات يتم للمجموعة التي phenone إضافة لفظ تحتوي على الفينل
Zahara Reply
what is organic chemistry
God Reply
what is thyroid land
lynda Reply
what is density
Fathmat Reply
A measure of the amount of matter contained by a given volume. The ratio of one quantity to that of another quantity.
Anoruo
mass divided by volume i.e. g/cm^3
Walter
A
lynda
what's molarity?
Okpaka Reply
the concentration of a substance in solution, expressed as the number moles of solute per litre of solution
Anoruo
Please help me solve this question. A is a solution of 0.995mol/dm cube hydrochloride acid. B was prepared by diluting 10cm cube of a saturated solution of sodium trioxocarbonate (iv) to 100cm cube at room temperature. Assuming that 21.50cm cube of A reacted with 25cm cube of B. Calculate: i. Concentration of solution B in mol/dm cube. ii.Solubility of sodium trioxocarbonate (iv) at room temperature. Equation of the reaction: Na2Co3 +2HCL------> 2NaCL +H2O +CO2.
Mercy Reply
I don't know whether it's ok or not, but the answers I got are: I. 0.428 mol/dm^3 II. 4.54g per 100 g of water
Nazifa
In the first one, I first found out the amount of HCl in mol using moles=concentration x volume. Then I checked the ratio of Na2CO3 to HCl, which is 0.5 to 1. Therefore the moles of Na2CO3 will be half of HCl. Using the amount in moles and the volume as 25 cm^3, I reached my answer!
Nazifa
In the second one, it says that 10 cm^3 has saturated Na2CO3 solution. Using the concentration we found in previous answer, I found out the moles present in 10cm^3. After that, using mass= moles x RFM, I got it's mass. As for the mass of water, we know 1 cm^3 gives 1g, so 10 cm^3 gives 10g.....
Nazifa
Using solubility= mass of solute/mass of solvent x 100, we reach the answer.
Nazifa
Note: we will not use the volume of solution to be 100 cm^3, because then the solution will be dilute.
Nazifa
plz do correct me if I'm wrong!! ☺️
Nazifa
is like the answer is 900
lynda
how can I make citric acid crystals from lemon juice
Traceyo Reply
Write the resonance hybrids of furan and thiophene
Hydrolysis of CH3CH2NO2 with 85% H2SO4 gives? 2/Acetaldehyde is oxidised with potassium dichromate and sulphuric acid gives 3/ When benzyl alcohol is oxidised with KMnO4, the product obtained ? 4/ Benzyl chloride is oxidised with KOH4, the 5/
Hydrolysis of CH3CH2NO2 with 85% H2SO4 gives?
Define reduction in term of loss or gain of oxygen or hydrogen give an example.
Aneela
CuO + Mg → Cu + MgO removing oxygen is reduction. here Mg is reducing agent(loss of electrons)
Haider
reduction >> reduc(+)ion mean (+)ion reduced mean electron gained by (+)ion (+)ion means H(+).
Haider
How what works
Eric Reply
no clue how this works is there a VERY SIMPLE tutorial
Stu Reply
what are double bonds
Hafsat Reply
double bond are 2 atom that share four electron they are typical covalent bond that occur in alkene for example c2 h4
abdulaziz
what is the differentiate property of alkynes
Fifa
Am new ,hope am warnly welcome
Sarah Reply
yes ur re welcome
icha
when you are sqaring exponetlias does the exponent become positive if it was negative?
Vittorio Reply

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Source:  OpenStax, Chemistry. OpenStax CNX. May 20, 2015 Download for free at http://legacy.cnx.org/content/col11760/1.9
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