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A molecule of Sulphuric Acid, H2SO4, consists of two atoms of hydrogen, one atom of sulphur and four atoms of oxygen
Sulphuric acid is a colourless viscous corrosive oily liquid, which has
- Melting Point : 10.3 degC
- Boiling Point : 338 degC
- Formula weight 98.08
- Specific gravity or density 1.94
- Flash point none
Sulphuric acid is the strong acid produced by dissolving sulphur trioxide in water.
SO3 + H2O ==> H2SO4
The Strength of Acids is determined by the degree to which they are ionised in aqueous solution.
For example, Sulphuric Acid, H2SO4, which is a strong acid is fully dissociated, and all the displaceable hydrogen in the acid is present in solution as Hydrogen Ion, H(+). H2SO4 ==> H(+) + SO4
100% as H(+)
In contrast, the weak acids ethanoic acid, CH3COOH, is partially ionised in solution, and only approximately 5% of the displaceable Hydrogen in the acid is present in solution as hydrogen ion, H(+).
Preparation of Sulphuric AcidCombustion of Sulphur
When a small amount of Sulphur, S, is kindled on a deflagrating spoon, it burns with a bright blue flame when introduced into a gas jar containing Oxygen, O2. A gas, Sulphur Dioxide, SO2, is the main product of the combustion. However, a little Sulphur Trioxide, SO3, is also formed, which makes the gas slightly cloudy.
S + O2 ==> SO2
Sulphur Dioxide
2S + 3O2 ==> 2SO3
Sulphur Trioxide
When shaken with water, the products of combustion dissolve, forming an acidic solution which turns litmus red.
Reactions of Sulphuric acidElectrolysis of a Solution of dilute Sulphuric Acid
The Electrolysis of an Aqueous Solution of dilute Sulphuric Acid is often carried out in a Hofmann Voltammeter, an apparatus in which the gases evolved at the anode and cathode can be collected in separate graduated tubes. When the solution is electrolyzed hydrogen is produced at the cathode and oxygen at the anode. These gases can be shown to be present in a 2 to 1 ratio and result from the electrolysis of water under acidic conditions.
Sulphuric acid is a strong electrolyte is fully dissociated in aqueous solution.
H2SO4 ==> 2 H(+) + SO4(2 -) Water is a weak electrolyte and is only slightly dissociated H2O ==> H(+) + OH(-) During electrolysis, the Hydrogen Ions, H(+), migrates towards the cathode, and are discharged there (i.e. they gain an electron and are converted to hydrogen gas). 2 H(+) + 2 e(-) ==> H2-
At the anode the concentration of Hydroxyl Ions, HO(-),is too low to maintain a reaction and the Sulphate Ions, SO4(2 -) are not oxidized but remain on in solution at the end. Water molecules must be the species reacting at the anode.
2 H2O ==> O2 + 4 H(+) + 4 e(-)
The overall reaction is
Cathode Reaction :
2 H(+) + 2e(-) ==> H2 4 H(+) + 4e(-) ==> 2H2
Anode Reaction :
2 H2O ==> O2 + 4 H(+) + 4 e(-)
Overall Cell Reaction:
4 H(+) + 2 H2O ==> 2 H2 + O2 + 4 H(+)
For every Hydrogen Ions, H(+), discharged at the anode, another hydrogen ion is formed at the cathode. The net result is that the concentration of the Sulphuric Acid, H2SO4, remains constant and this electrolysis consists of the decomposition of water with the overall reaction
2H2O ==> 2H2- + O2-
Ferrous Sulphate, Fe(II)SO4, is the salt formed when Iron, Fe, is dissolved in Sulphuric Acid, H2SO4.
Hydrogen Chloride, HCl, may be prepared in the laboratory by heating Concentrated Sulphuric Acid, H2SO4, with Sodium Chloride, NaCl.
NaCl + H2SO4 ==> NaHSO4 + HCl
Many Metallic Chlorides liberate Chlorine, Cl2, when treated with Sulphuric Acid, H2SO4, and Manganese Dioxide, MnO2).
Many Metallic Chlorides liberate Hydrogen Chloride gas, HCl, when warmed with concentrated Sulphuric Acid, H2SO4.
Sulphur Trioxide, SO3, is prepared by heating concentrated Sulphuric Acid, H2SO4, with a large excess of Phosphorus Pentoxide, P2O5.
H2SO4 + P2O5 ==> SO3 + 2 HPO3
Sulphur Dioxide, SO2, is usually made in the laboratory by heating concentrated Sulphuric Acid, H2SO4, with Copper turnings, Cu.
Cu + 2 H2SO4 ==> CuSO4 + SO2 + 2 H2O
Hydrogen Fluoride, HF, can be prepared in the laboratory by heating Concentrated Sulphuric Acid, H2SO4, with Calcium Fluoride, CaF2.
H2SO4 + CaF2 ==> 2 HF + CaSO4
Hydrogen Iodide, HI, can be prepared by direct combination of the elements using a platinum catalyst. In the laboratory it is prepared by heating Concentrated Sulphuric Acid, H2SO4, with Sodium Iodide, NaI.
H2SO4 + 2 NaI ==> 2 HI + Na2SO4
Methanol, CH3OH, does not undergo dehydration reactions. Instead, in reaction with Sulphuric Acid, H2SO4, the ester, Dimethyl Sulphate, (CH3)2SO4, is formed.
concentrated H2SO4 2CH3OH ==> (CH3)2SO4 + H2O Methanol Dimethyl Water Sulphate
Sulphuric Acid, H2SO4, absorbs Ethylene, C2H4, at room temperature to form Ethyl Hydrogen Sulphate, C2H5.HSO4, with much evolution of heat.
C2H4 + H2SO4 ==> C2H5.HSO4
If this is treated with Water, H2O and warmed, Ethanol, C2H5OH, is formed.
heat C2H5.HSO4 + H2O ==> C2H5OH + H2SO4
Zinc, Zn, is a transition metallic element found in Group IIb of the Periodic Table.
- Atomic Number : 30
- Relative Atomic Mass : 65.38
Zinc was known from ancient times, when Brass (i.e. an alloy of Copper and Zinc) was used. Lohneyes was the first to apply the term "Zinc" correctly to the metal that we know today in 1697AD.
OccurrenceZinc is found in different ore forms, including
- Zinc Spar, ZnCO3,
- Calamine, ZnCO3,
- Zinc Blande, ZnS,
- Zincite, ZnO,
- Willemite, 2ZnO.SiO2,
- Franklinite, (ZnFe)O.Fe2O3, and
- Zinc Spinel, ZnO.Al2O3.
Zinc is extracted using two process :
- Roasting, which involves the preparation of zinc oxide and
- Reduction, with charcoal which involves the release of the zinc from the oxide. PropertiesZinc is
- a bright bluish-white metal, which is brittle at room temperature.
- is slowly oxidised in moist air.
- is an good conductor of heat and electricity.
- Zinc burns in air at 1000 degC to form a bulky mass of zinc oxide which is known as Philosopher's Wool.
- Zinc reacts with dilute acids, with the liberation of hydrogen.
Zn + H2SO4 ==> ZnSO4 + H2
- Zinc in the presence of dilute acid is a powerful reducing agent, probably due to Nascent Hydrogen, H*, liberated in the reaction being a better reducing agent than hydrogen gas.
- Zincis amphoteric and forms salts with alkalis. For example, Zinc dissolves in hot concentrated caustic soda solution with the liberation of hydrogen gas and the formation of sodium zincate.
Zn + 2 NaOH ==> Na2ZnO2 + H2
UsesZinc is in widespread use- in the manufacture of electric cells (i.e. Dry Cells),
- in the manufacture of galvanized iron sheets, to protect against corrosion of the iron,
- in the manufacture of die-castings objects (e.g. the carburettor in car engines),
- in alloys,
- in medicine (as the Oxide), and
- as a filler for Rubber and in Paints.
What else can I help you with?
What are the two basic parts of a chemical reaction?
Chemical reaction is the making and breaking of chemical bonds, leading to changes in the composition of matter. Chemical reactions do not create or destroy matter; they only rearrange it in various ways.
If making ammonia from nitrogen and hydrogen A chemical or physical change?
Making ammonia from nitrogen and hydrogen is a chemical change because it involves a rearrangement of the atoms in the reactants to form new chemical compounds in the product (ammonia). This process is characterized by the breaking and forming of chemical bonds.
Why concept of limiting reactant is not applied to reversible reaction?
Concept of limiting reactant is not applicable to the reversible reactions because in these reactions all the reactants are converted into products and no reactants remain at the end of the reaction.
What does chemical reaction have to do with making and breaking bonds?
Chemical reactions involve the breaking of bonds in reactant molecules and the formation of new bonds in product molecules. During a reaction, old bonds are broken as energy is absorbed, and new bonds are formed as energy is released. The breaking and forming of chemical bonds are essential for rearranging atoms and creating new substances during a reaction.
Increasing what speeds up most chemical reactions?
That would depend highly on the type of chemical reaction. Usually increasing the speed of the molecules by heating, stirring, etc has some effect. However, not all reactions are benefited by this. An example is the formation of carbonic acid. A solution of weak carbonic acid is formed by dissolving carbon dioxide gas in water. Warmer water is incapable of dissolving as much carbon dioxide as cold water and stirring/agitating the water only speeds up the loss of carbon dioxide. Increasing the concentration of reactants usually has good effect, but can be dangerous. Be sure of any reaction BEFORE preforming it.
What are the two basic parts of a chemical reaction?
Chemical reaction is the making and breaking of chemical bonds, leading to changes in the composition of matter. Chemical reactions do not create or destroy matter; they only rearrange it in various ways.
What is the difference between the bond enthalpy of the reactants and the bond enthalpy of the products in a chemical reaction?
The difference between the bond enthalpy of the reactants and the bond enthalpy of the products in a chemical reaction represents the energy change that occurs during the reaction. If the bond enthalpy of the products is lower than that of the reactants, it indicates that energy is released during the reaction, making it exothermic. Conversely, if the bond enthalpy of the products is higher than that of the reactants, it indicates that energy is absorbed during the reaction, making it endothermic.
How can you realise a chemical reaction?
By making interact under certain conditions of temperature, pressure, concentration, etc. the reactants.
What is a description of a reaction using chemical symbols?
It is called a chemical equation. The reactantsengage in a chemical change and result in different chemical products being created. Some reactions have catalystswhich undergo no net change after the reaction.
How can one predict the products of a chemical reaction?
To predict the products of a chemical reaction, one must understand the reactants involved and their chemical properties. This can be done by applying knowledge of chemical bonding, reaction types, and balancing chemical equations. Additionally, using tools such as the periodic table and reaction mechanisms can help in making accurate predictions.
In a chemical reaction a catalyst changes the 1.potential energy of the products 2.potential energy of the reactants 3. heat of reaction 4.activation energy?
A catalyst lowers the activation energy of a reaction, making it easier for the reactants to form products. It does not change the potential energy of the reactants or products, nor does it affect the overall heat of the reaction.
What happens to the bonds of the products during a chemical reaction?
Chemical reactions always involve changes in the chemical bonds that join atoms in compounds. At least one chemical bond is broken or formed during a chemical reaction.
How do enzymes alter the equilibrium of a chemical reaction?
Enzymes alter the equilibrium of a chemical reaction by lowering the activation energy required for the reaction to occur, thus speeding up the rate at which the reaction reaches equilibrium. This is achieved by stabilizing the transition state of the reaction, making it easier for the reactants to form products.
What factors contribute to making a chemical reaction energetically favorable?
Several factors contribute to making a chemical reaction energetically favorable, including the difference in energy between reactants and products, the stability of the products formed, and the presence of catalysts that lower the activation energy required for the reaction to occur. Additionally, the entropy change of the system and the temperature at which the reaction takes place can also influence the favorability of a chemical reaction.
Is making making crisps from cooking oil potatoes a chemical reaction?
Yes, it is a chemical reaction.
What speeds up chemical reactions?
to speed up a chemical reaction .. we use a catalyst
How can one predict the product of a chemical reaction?
To predict the product of a chemical reaction, one must understand the reactants involved and their chemical properties. This can be done by applying knowledge of chemical reactions, balancing equations, and considering factors such as the type of reaction and the reactivity of the elements or compounds involved. Additionally, using tools like reaction prediction software or consulting reference materials can help in making accurate predictions.
