Indicate if a precipitate forms by completing each equation as a net ionic equation.
So state if there is no reaction.
The net ionic equation can be used to determine if a precipitate forms when the following compounds are mixed.
So state if there is no reaction.
The mixture of white BaSO41s2 and black CuS remains in the solution.
If you apply the guidelines in Table 5.1, you will be able to tell whether each of the following is water or insoluble.
AgCl is an ionic compound with low solubility in water.
AgCl is a strong electrolyte if we only focus on the degree of dissociation.
A strong electrolyte is a substance that when dissolved in water gives a solution that is a good conductor of electricity.
A solution of AgCl is not a good conductor of electricity because of its low solubility in water.
Some chemists argue that AgCl is a strong electrolyte because it is 100% dissociated in the solution, while others argue that it is a weak electrolyte because it is not a good conductor of electricity.
Not at all, because all chemists agree on the following facts: AgCl is not a good conductor of electricity, only a small amount of AgCl can be dissolved in water, and an aqueous solution of AgCl is not a good conductor of electricity.
The acid-base concept is a major theme in chemistry.
In this section, we emphasize the view proposed by Svante Arrhenius in 1884 but also introduce a more modern theory proposed in 1923 by Thomas Lowry and Johannes Bronsted.
In 1884, this definition was first proposed by Svante Arrhenius.
Strong acids that include hydrogen to one H2O molecule are examples.
The ion H3O+ can be represented by the following equation.
According to the equation, HCl is a strong electrolyte in water and that all the HCl molecule are converted into hydrated H+ and Cl- ion.
The red color of the acid-base indicator shows the acidic nature of lemon juice.
The basic nature of soap can be seen by the change in the color of the an Loon indicator from red to yellow.
When the strong acid HNO3 is dissolved in water, complete ionization into Strong Acids occurs.
Strong Bases only have a short list of common strong acids.
Table 5.2 contains the list of common strong acids.
You need to memorize this list.
The calculations will be put off until Chapter 16.
There is a lot of experimental evidence that proves this is not the case.
The transfer of an H+ ion from one electron to a hydrogen atom was proposed by Britain in 1923.
H+ hydrogen ion, H+, is a protons when acids are dissolved in water.
The acid and water are acting as donors and acceptors in the equations.
It is a matter of preference if we include water in the equation for the reaction that occurs when an acid is dissolved in water.
Some chemists prefer to write the reaction without water as a reactant, as we did in equations (5.10), to eliminate the "extra" water molecule.
You must remember that the H+ ion is bound to a water molecule and is not a free protons in solution.
Many chemists prefer to include H2O as a reactant in order to emphasize that the reactions actually involve the transfer of protons from acid molecule to water molecule.
We can identify bases through their bitter taste, slippery feel, and effect on the colors of acid-base indicators.
Consider a ionic acid, such as NaOH.
When the solid is in water, the ionizes.
Na+(aq) plus OH-(aq) is the best representation.
The number of strong bases is small.
They are mostly the hydroxides of group 1 and 2 metals.
The list should be memorised.
Some substances react with water, not just by dissolving in it.
Ammonia is also a base.
NH molecule ionize.
NH is a weak electrolyte.
Basic substances are weak bases in the same way NH4 is with water.
The ball-and-stick model of the Bronsted-Lowry theory focuses on the transfer of protons from one substance to another.
When water is dissolved in an acid, it creates H+ ion and a base produces ion.
The experiment shows that small amounts of H+ OH and OH- ion are present in pure water.
A double arrow 1D2 is used instead of a single arrow 1!2 because of the limited Ammonium ion reaction.
The measurement shows that 3H+4water is 1.0 * 10-7 M at 25 degC.
Pure water has a lower concentration of H+ ion than an acidic solution.
A solution of base will have 3 OH-4 7 1.0 * 10-7 M at 25 degrees.
The ideas are summarized.
An acidic solution has some water in it.
A basic solution has water.
The statements can be used in a different way.
An acidic solution has an excess of H+ ion and a basic solution has an excess of OH- ion.
We will encounter these ideas again in Chapter 16.
The ability of acids and bases to cancel or neutralize each other is perhaps the most significant property of acids and bases.
The neutralization of a strong acid by a strong base is shown in the net ionic equation.
When the neutralization reaction is weak, the situation is different.
H+ + CH COO-
The base is combined with CH COOH molecules.
There is a neutralization involving a weak base and a strong acid.
NH4OH is a form of NH +.
The neutralization reactions involve strong acids.
We use a single arrow 1!2 instead of a double arrow 1D2 in the equations for these reactions.
Ionizable H atoms are separated from other H atoms in the formula by either writing them first in the formula or by indicating where they are located in the molecule.
There are two ways to show that one H atom in the acetic acid molecule is ionizable.
Methane has four H atoms, but they are not ionizable.
CH4 is not an acid or a base.
A substance with a formula that indicates a combination of OH- ion with cations is a strong base.
We usually need a chemical equation for the ionized reaction to identify a weak base.
NH3 is the only weak base we will work with.
CH3 CH2OH is not a base.
The OH group is not present in either pure or aqueous solutions.
This compound is quite insol uble in water and is a base.
The suspension of water that is the familiar milk of magnesia is made from finely divided solid particles.
Some OH Mg1OH221s2 was produced in the suspension.
More dissolved to produce more OH Mg1OH221s2 in solution, which is neutralized by more H+.
A weak acid, such as acetic acid, reacts with Mg1OH221s2.
acetic acid is written in its form in the net ionic equation.
The CH3COO H+ ion is always present in an acetic acid solution.
The Mg1OH22 will be dissolved if there is enough acetic acid.
The equation for the reaction is given.
Calcium carbonate, which is found in limestone and marble, is a strong and weak acid.
Carbonic acid, H2CO3 is a very unstable substance that degrades into H2O Presselect and CO21g2.
Figure 5-11 is given below.
When CaCO erodes by acid rain, a gas is given off.
The erosion of marble is caused by the reaction represented by equation.
CaCO marble through the reaction 31s2 has the ability to neutralize acids.
There are several anions and one cation that produce gases in acid-base reactions.
The reactions are neutralization reactions, which means they are of the general form acid + base.
We can start with the whole formula equation, switch to the ionic equation, and then remove the spectator ion to arrive at the net ionic equation.
When the neutralization reaction involves a strong acid and a weak base, the net ionic equation is H2O1l2.
The net ionic equation includes a solid because the base was not soluble.
The reaction of ammonia with propionic acid is represented by a net ionic equation.
The neutralization reaction will be completed.
The hard water deposits found in coffee makers are composed of calcium carbonate.
A solution of acetic acid and water is commonly used to remove deposits.
Write an equation for a reaction.
The neutralization reaction will be completed.
Practical applications of oxidation-reduction reactions can be traced back to when metal tools were first made.
The metal was obtained by heating copper.
In the presence of their oxides by carbon, cuprite 1Cu2O2 or hematite 1Fe2O32 are examples of metal ores.
Iron has become the most widely used metal for the removal of oxygen.
The equation for the reaction is given below.
We can think of the CO1g2 as taking O atoms away from Fe.
To make CO21g2 and the free element iron.
CO1g2 is reduced and Fe2O31s2 is reduced.
Oxygen can be removed by igniting a finely instead of oxidation-reduction.
Railway workers use finely divided Fe2O3 and Al to make liquid iron for welding together iron railway tracks.
The transfer of O atoms is the basis of oxidation and reduction.
Even when no oxygen is involved, many reactions can be described as oxidation-reduction reactions.
CO2 is producing Al2O3.
The changes of Al2O31s2 + 2 Fe1l2 iron are shown in red.
Even though we assess oxidation state changes by element, oxidation and reduction involve the entire species in which the element is found.
The whole compound Fe2O3 is reduced, not just the Fe atoms, but the CO as well.
Do you know if each of the following is an oxidation-reduction reaction?
Look for changes in the oxidation states of the elements on both sides of the equation.