Carbon dioxide chemical properties equation. Basic chemical properties of carbon dioxide
Learning objectives: - To study the action of acids on carbonates and draw general conclusions.
Understand and perform qualitative carbon dioxide testing.
Expected results: Through a chemical experiment, based on observations, analysis of the results of the experiment, students draw conclusions about the methods of obtaining carbon dioxide, its properties, and the effect of carbon dioxide on lime water. By comparing the methods for producing hydrogen and carbon dioxide by the action of dilute acids on metals and carbonates,Students draw conclusions about the various products of chemical reactions obtained by the action of dilute acids.
During the classes:
Organizing time: 1) Greeting. 2) Definition of absent. 3) Checking the readiness of students and the classroom for the lesson
Poll homework: Presentation of the video on the topic: "Simple chemical reactions, hydrogen.Carrying out mutual assessment of homework, the “Two stars and one wish” technique. Purpose: Mutual assessment, repetition of the studied material on the topic of simple chemical reactions; hydrogen production methods and properties.
Divide the class into groups. Strategy: one by one.
Learning new material . Organizes work in groups to study a theoretical resource on the topic of simple chemical reactions - carbon dioxide, obtaining and studying the properties of carbon dioxide. The teacher organizes mutual control of the studied,FD – Technics - Make up one sentence in which it is necessary to express the answer to the question posed by the teacher.
- What new did you learn about the properties of acids?
What did you learn about carbon dioxide?
Purpose: aboutAppreciate the quality of each response quickly and overall.To note whether the students identify the main concepts of the material covered and their relationship.
The teacher organizes a repetition of safety rules when working with acids and alkalis (lime water) - chemical dictation - 4 min.FO - Technics - self-control according to the model - insert missing words, work with text. The goal is to check the level of knowledge of the rules for conducting a safe experiment.
Dictation
WORK SAFETY WITH ACIDS
acids cause a chemical ………………….skinand other fabrics.
According to the speed of action and the rate of destruction of body tissues, acids are arranged in the following order, starting with the moststrong: ……………………………………………………………………………………………………………………………… ……………………………………………………………………………………………………………………………………… …………………………………………
When diluting acids, ……………… pour over ………………… a stick with a safety rubber ring at the bottom.
A bottle of acid is not allowed ………………hands to the chest, because possibly ………………… and …………..
First aid. Acid-affected area of skin ……….jet of cold ………….. during ………………. min. posle ………………… soaked water is applied to the burnt placesolution …………. gauze bandage or waddingswab. In 10 minutes. bandage ……….., skin ………….,and lubricated with glycerin to reduce pain sensationsscheny.
Performing a laboratory experiment: "Obtaining carbon dioxide and studying its properties."
Students perform an experimentfill in the table of observations and conclusions,record video of observations for placement inYouTubefor their parents to see.
Reflection of the lesson: teacherasks to express their attitude to the forms of the lesson, to express their wishes for the lesson.Students fill in colored stickers - "Traffic Light"
"Red" - the topic is not clear to me, there are many questions left.
"Yellow" - the topic is clear to me, but there are questions.
"Green" - the theme is clear to me.
Homework : Study the theoretical resource. To compare in writing the results of the action of dilute acids on metals and carbonates, to compare the gases hydrogen and carbon dioxide - a mini-essay.Make a video and post it onYouTube. Groups to rate other students' videosFO - technique - "Two stars and one wish."
References:
Active methods of teaching and learningwww. CPM. KZ
Formative assessment in elementary school.A practical guide for teachers / Comp. O. I. Dudkina, A. A. Burkitova, R. Kh. Shakirov. - B .: "Bilim", 2012. - 89 p.
Evaluation of educational achievements of students.Methodological guide / Compiled by R. Kh. Shakirov, A.A. Burkitova, O.I. Dudkin. - B .: "Bilim", 2012. - 80 p.
Appendix 1
Theoretical resource
Carbon dioxide
CO molecule 2
Physical properties
Carbon monoxide (IV) - carbon dioxide, colorless and odorless gas, heavier than air, soluble in water, upon strong cooling it crystallizes in the form of a white snow-like mass - “dry ice”. At atmospheric pressure, it does not melt,and evaporates, bypassing the liquid state of aggregation - this phenomenon is called sublimation , sublimation temperature -78 °С. Carbon dioxide is formed during the decay and combustion of organic matter. Contained in the air and mineral springs, released during the respiration of animals and plants. Slightly soluble in water (1 volume of carbon dioxide in one volume of water at 15 °C).
Receipt
Carbon dioxide is produced by the action of strong acids on carbonates:
metal carbonate+ acid →a salt + carbon dioxide + water
CaCO 3 + 2HCl = CaCl 2 + CO 2 + H 2 O
carbonatecalcium + hydrochloricacid = carbonicgas + water
calcium carbonate + hydrochloric acid→ calcium chloride + carbon dioxide + water
Na 2 CO 3 + 2HCl = 2NaCl + CO 2 + H 2 O
carbonatesodium +
hydrochloricacid =
carbonicgas +
water
sodium carbonate + hydrochloric acid→ sodium chloride + carbon dioxide + water
Chemical properties
Qualitative reaction
A qualitative reaction for the detection of carbon dioxide is the turbidity of lime water:
Ca(OH) 2 + CO 2 = CaCO 3 ↓ + H 2 Oh
lime water + carbon dioxide = 
+ water
At the beginning of the reaction, a white precipitate is formed, which disappears when CO is passed for a long time. 2 through lime water, because insoluble calcium carbonate is converted to soluble bicarbonate:
CaCO 3 + H 2 O+CO 2 = With a(HCO 3 ) 2 .
Appendix 2
Laboratory experiment No. 7
"Production of carbon dioxide and its recognition"
Objective: experimentally obtain carbon dioxide and conduct an experiment characterizing its properties.
Equipment and reagents: stand with test tubes, laboratory stand, test tubes, vent tube with rubber stopper, device for obtaining carbon dioxide, chalk (calcium carbonate), copper carbonate ( II ), sodium carbonate, acetic acid solution, lime water.
Working process:
Prepare in advance a test tube with 3 ml of lime water.
Assemble the device for obtaining gas (as shown in figure 1). Place a few pieces of chalk into the test tube, pour up to 1/3 of the volume of the test tube with acetic acid and close the cork with a gas outlet tube, the end of which is directed downwards. Describe how carbon dioxide is produced_______________________?) .
Immerse the vent tube into the lime water tube so that the end of the vent tube is below the level of the solution. Pass carbon dioxide until precipitation occurs. If you continue to pass carbon dioxide further, the precipitate will disappear. Describe the chemical properties of carbon dioxide.
Based on the results of the experiments, fill in the table, draw a conclusion.
Work sample
They assembled a device for producing carbon dioxide, placed pieces of chalk in a test tube and added hydrochloric acid. Observe: the release of gas bubbles.
Carbon dioxide can be obtained by the action of acetic acid on:
chalk (carbonate Conclusion: Received carbon dioxide and studied its properties.
carbon dioxide (carbon dioxide), also called carbonic acid, is the most important component in the composition of carbonated drinks. It determines the taste and biological stability of drinks, gives them sparkling and refreshing properties.
Chemical properties. Chemically, carbon dioxide is inert. Formed with the release of a large amount of heat, it, as a product of the complete oxidation of carbon, is very stable. Carbon dioxide reduction reactions proceed only at high temperatures. So, for example, interacting with potassium at 230 ° C, carbon dioxide is reduced to oxalic acid:
Entering into chemical interaction with water, gas, in an amount of not more than 1% of its content in solution, forms carbonic acid, dissociating into ions H +, HCO 3 -, CO 2 3-. In an aqueous solution, carbon dioxide easily enters into chemical reactions, forming various carbonic salts. Therefore, an aqueous solution of carbon dioxide is highly aggressive towards metals, and also has a destructive effect on concrete.
physical properties. Carbon dioxide is used to saturate drinks, liquefied by compression to high pressure. Depending on temperature and pressure, carbon dioxide can also be in a gaseous or solid state. The temperature and pressure corresponding to a given state of aggregation are shown in the phase equilibrium diagram (Fig. 13).
At a temperature of minus 56.6 ° C and a pressure of 0.52 MN / m 2 (5.28 kg / cm 2), corresponding to the triple point, carbon dioxide can simultaneously be in a gaseous, liquid and solid state. At higher temperatures and pressures, carbon dioxide is in a liquid and gaseous state; at a temperature and pressure that are below these indicators, the gas, directly bypassing the liquid phase, passes into the gaseous state (sublimes). Above the critical temperature of 31.5°C, no amount of pressure can hold carbon dioxide as a liquid.
In the gaseous state, carbon dioxide is colorless, odorless and has a slightly sour taste. At a temperature of 0 ° C and atmospheric pressure, the density of carbon dioxide is 1.9769 kg / l 3; it is 1.529 times heavier than air. At 0°C and atmospheric pressure, 1 kg of gas occupies a volume of 506 liters. The relationship between the volume, temperature and pressure of carbon dioxide is expressed by the equation:
where V is the volume of 1 kg of gas in m 3 / kg; T is the gas temperature in °K; P - gas pressure in N / m 2; R is the gas constant; A is an additional value that takes into account the deviation from the equation of state of an ideal gas;
Liquefied carbon dioxide- a colorless, transparent, easily mobile liquid, resembling alcohol or ether in appearance. The density of a liquid at 0°C is 0.947. At a temperature of 20°C, the liquefied gas is stored at a pressure of 6.37 MN/m 2 (65 kg/cm 2) in steel cylinders. With free flow from the balloon, the liquid evaporates with the absorption of a large amount of heat. When the temperature drops to minus 78.5 ° C, part of the liquid freezes, turning into the so-called dry ice. In terms of hardness, dry ice is close to chalk and has a dull white color. Dry ice evaporates more slowly than liquid, and it directly turns into a gaseous state.
At a temperature of minus 78.9 ° C and a pressure of 1 kg / cm 2 (9.8 MN / m 2), the heat of sublimation of dry ice is 136.89 kcal / kg (573.57 kJ / kg).
The interaction of carbon with carbon dioxide proceeds according to the reaction
The system under consideration consists of two phases, solid carbon and gas (f = 2). Three interacting substances are interconnected by one reaction equation, therefore, the number of independent components is k = 2. According to the Gibbs phase rule, the number of degrees of freedom of the system will be equal to
C \u003d 2 + 2 - 2 \u003d 2.
This means that the equilibrium concentrations of CO and CO 2 are functions of temperature and pressure.
Reaction (2.1) is endothermic. Therefore, according to the principle of Le Chatelier, an increase in temperature shifts the equilibrium of the reaction in the direction of the formation of an additional amount of CO.
During the course of reaction (2.1), 1 mol of CO 2 is consumed, which under normal conditions has a volume of 22400 cm 3, and 1 mol of solid carbon with a volume of 5.5 cm 3. As a result of the reaction, 2 moles of CO are formed, the volume of which under normal conditions is 44800 cm 3.
From the above data on the change in the volume of reagents during reaction (2.1), it follows:
- The transformation under consideration is accompanied by an increase in the volume of interacting substances. Therefore, in accordance with Le Chatelier's principle, an increase in pressure will promote the reaction in the direction of formation of CO 2 .
- The change in the volume of the solid phase is negligible compared to the change in the volume of the gas. Therefore, for heterogeneous reactions involving gaseous substances, it can be assumed with sufficient accuracy that the change in the volume of interacting substances is determined only by the number of moles of gaseous substances in the right and left parts of the reaction equation.
The equilibrium constant of the reaction (2.1) is determined from the expression
If graphite is taken as the standard state in determining the activity of carbon, then a C = 1
The numerical value of the equilibrium constant of reaction (2.1) can be determined from the equation
Data on the effect of temperature on the value of the equilibrium constant of the reaction are given in Table 2.1.
Table 2.1– Values of the equilibrium constant of reaction (2.1) at different temperatures
From the given data it can be seen that at a temperature of about 1000K (700 o C) the equilibrium constant of the reaction is close to unity. This means that reaction (2.1) is almost completely reversible at moderate temperatures. At high temperatures, the reaction proceeds irreversibly in the direction of CO formation, and at low temperatures in the opposite direction.
If the gas phase consists only of CO and CO 2 , by expressing the partial pressures of the interacting substances in terms of their volumetric concentrations, equation (2.4) can be reduced to the form
In industrial conditions, CO and CO 2 are obtained as a result of the interaction of carbon with oxygen in air or blast enriched with oxygen. At the same time, another component, nitrogen, appears in the system. The introduction of nitrogen into the gas mixture affects the ratio of the equilibrium concentrations of CO and CO 2 similarly to a decrease in pressure.
Equation (2.6) shows that the composition of the equilibrium gas mixture is a function of temperature and pressure. Therefore, the solution of equation (2.6) is graphically interpreted using a surface in three-dimensional space in the coordinates T, Ptot and (% CO). The perception of such dependence is difficult. It is much more convenient to represent it as a dependence of the composition of an equilibrium mixture of gases on one of the variables, with the second of the system parameters being constant. As an example, Figure 2.1 shows data on the effect of temperature on the composition of an equilibrium gas mixture at Ptot = 10 5 Pa.
With a known initial composition of the gas mixture, the direction of reaction (2.1) can be judged using the equation
If the pressure in the system remains unchanged, relation (2.7) can be reduced to the form
Figure 2.1- Dependence of the equilibrium composition of the gas phase for the reaction C + CO 2 = 2CO on temperature at P CO + P CO 2 = 10 5 Pa.
For a gas mixture whose composition corresponds to point a in Figure 2.1, . Wherein
and G > 0. Thus, the points above the equilibrium curve characterize systems whose approach to the state of thermodynamic equilibrium proceeds by the reaction
Similarly, it can be shown that the points below the equilibrium curve characterize systems that approach the equilibrium state by the reaction
DEFINITION
Carbon dioxide(carbon dioxide, carbonic anhydride, carbon dioxide) - carbon monoxide (IV).
Formula - CO 2. Molar mass - 44 g / mol.
Chemical properties of carbon dioxide
Carbon dioxide belongs to the class of acidic oxides, i.e. when interacting with water, it forms an acid called carbonic acid. Carbonic acid is chemically unstable and at the moment of formation it immediately decomposes into components, i.e. The reaction of the interaction of carbon dioxide with water is reversible:
CO 2 + H 2 O ↔ CO 2 × H 2 O(solution) ↔ H 2 CO 3 .
When heated, carbon dioxide breaks down into carbon monoxide and oxygen:
2CO 2 \u003d 2CO + O 2.
As with all acidic oxides, carbon dioxide is characterized by reactions of interaction with basic oxides (formed only by active metals) and bases:
CaO + CO 2 \u003d CaCO 3;
Al 2 O 3 + 3CO 2 \u003d Al 2 (CO 3) 3;
CO 2 + NaOH (dilute) = NaHCO 3 ;
CO 2 + 2NaOH (conc) \u003d Na 2 CO 3 + H 2 O.
Carbon dioxide does not support combustion; only active metals burn in it:
CO 2 + 2Mg \u003d C + 2MgO (t);
CO 2 + 2Ca \u003d C + 2CaO (t).
Carbon dioxide enters into reactions with simple substances such as hydrogen and carbon:
CO 2 + 4H 2 \u003d CH 4 + 2H 2 O (t, kat \u003d Cu 2 O);
CO 2 + C \u003d 2CO (t).
When carbon dioxide interacts with peroxides of active metals, carbonates are formed and oxygen is released:
2CO 2 + 2Na 2 O 2 \u003d 2Na 2 CO 3 + O 2.
A qualitative reaction to carbon dioxide is the reaction of its interaction with lime water (milk), i.e. with calcium hydroxide, in which a white precipitate is formed - calcium carbonate:
CO 2 + Ca (OH) 2 \u003d CaCO 3 ↓ + H 2 O.
Physical properties of carbon dioxide
Carbon dioxide is a colorless and odorless gaseous substance. Heavier than air. Thermally stable. When compressed and cooled, it easily transforms into liquid and solid states. Carbon dioxide in a solid state of aggregation is called "dry ice" and easily sublimates at room temperature. Carbon dioxide is poorly soluble in water and partially reacts with it. Density - 1.977 g / l.
Obtaining and using carbon dioxide
Allocate industrial and laboratory methods for producing carbon dioxide. So, in industry it is obtained by roasting limestone (1), and in the laboratory - by the action of strong acids on carbonic acid salts (2):
CaCO 3 \u003d CaO + CO 2 (t) (1);
CaCO 3 + 2HCl \u003d CaCl 2 + CO 2 + H 2 O (2).
Carbon dioxide is used in food (carbonation of lemonade), chemical (temperature control in the production of synthetic fibers), metallurgical (environmental protection, such as brown gas precipitation) and other industries.
Examples of problem solving
EXAMPLE 1
| Exercise | What volume of carbon dioxide will be released under the action of 200 g of a 10% solution of nitric acid on 90 g of calcium carbonate containing 8% impurities insoluble in acid? |
| Decision | The molar masses of nitric acid and calcium carbonate, calculated using the table of chemical elements of D.I. Mendeleev - 63 and 100 g/mol, respectively. We write the equation for the dissolution of limestone in nitric acid: CaCO 3 + 2HNO 3 → Ca(NO 3) 2 + CO 2 + H 2 O. ω(CaCO 3) cl \u003d 100% - ω admixture \u003d 100% - 8% \u003d 92% \u003d 0.92. Then, the mass of pure calcium carbonate is: m(CaCO 3) cl = m limestone × ω(CaCO 3) cl / 100%; m(CaCO 3) cl \u003d 90 × 92 / 100% \u003d 82.8 g. The amount of calcium carbonate substance is: n (CaCO 3) \u003d m (CaCO 3) cl / M (CaCO 3); n (CaCO 3) \u003d 82.8 / 100 \u003d 0.83 mol. The mass of nitric acid in solution will be equal to: m(HNO 3) = m(HNO 3) solution × ω(HNO 3) / 100%; m (HNO 3) \u003d 200 × 10 / 100% \u003d 20 g. The amount of calcium nitric acid substance is: n(HNO 3) = m(HNO 3) / M(HNO 3); n (HNO 3) \u003d 20/63 \u003d 0.32 mol. Comparing the amounts of substances that have entered into the reaction, we determine that nitric acid is in short supply, therefore, we make further calculations for nitric acid. According to the reaction equation n (HNO 3): n (CO 2) \u003d 2: 1, therefore n (CO 2) \u003d 1 / 2 × n (HNO 3) \u003d 0.16 mol. Then, the volume of carbon dioxide will be equal to: V(CO 2) = n(CO 2)×V m ; V(CO 2) \u003d 0.16 × 22.4 \u003d 3.58 g. |
| Answer | The volume of carbon dioxide is 3.58 g. |
Let's imagine the following situation:
You work in a lab and decide to do an experiment. To do this, you opened the cabinet with reagents and suddenly saw the following picture on one of the shelves. Two jars of reagents had their labels peeled off, which were safely left lying nearby. At the same time, it is no longer possible to determine exactly which jar corresponds to which label, and the external signs of the substances by which they could be distinguished are the same.
In this case, the problem can be solved using the so-called qualitative reactions.
Qualitative reactions called such reactions that allow you to distinguish one substance from another, as well as to find out the qualitative composition of unknown substances.
For example, it is known that the cations of some metals, when their salts are added to the burner flame, color it in a certain color:
This method can only work if the substances to be distinguished change the color of the flame in different ways, or one of them does not change color at all.
But, let's say, as luck would have it, the substances you determine do not color the color of the flame, or they color it in the same color.
In these cases, it will be necessary to distinguish substances using other reagents.
In what case can we distinguish one substance from another with the help of any reagent?
There are two options:
- One substance reacts with the added reagent, while the other does not. At the same time, it must be clearly seen that the reaction of one of the starting substances with the added reagent has really passed, that is, some external sign of it is observed - a precipitate precipitated, gas was released, a color change occurred, etc.
For example, it is impossible to distinguish water from a sodium hydroxide solution using hydrochloric acid, despite the fact that alkalis react perfectly with acids:
NaOH + HCl \u003d NaCl + H 2 O
This is due to the absence of any external signs of a reaction. A transparent colorless solution of hydrochloric acid, when mixed with a colorless hydroxide solution, forms the same transparent solution:
But on the other hand, water can be distinguished from an aqueous solution of alkali, for example, using a solution of magnesium chloride - a white precipitate forms in this reaction:
2NaOH + MgCl 2 = Mg(OH) 2 ↓+ 2NaCl
2) substances can also be distinguished from each other if they both react with the added reagent, but do so in different ways.
For example, a solution of sodium carbonate can be distinguished from a solution of silver nitrate using a solution of hydrochloric acid.
hydrochloric acid reacts with sodium carbonate to release a colorless, odorless gas - carbon dioxide (CO 2):
2HCl + Na 2 CO 3 \u003d 2NaCl + H 2 O + CO 2
and with silver nitrate to form a white cheesy precipitate AgCl
HCl + AgNO 3 \u003d HNO 3 + AgCl ↓
The tables below show different options for detecting specific ions:
Qualitative reactions to cations
| Cation | Reagent | Sign of reaction |
| Ba 2+ | SO 4 2- |
Ba 2+ + SO 4 2- \u003d BaSO 4 ↓ |
| Cu2+ | 1) Precipitation of blue color: Cu 2+ + 2OH - \u003d Cu (OH) 2 ↓ 2) Precipitation of black color: Cu 2+ + S 2- \u003d CuS ↓ |
|
| Pb 2+ | S2- | Precipitation of black color: Pb 2+ + S 2- = PbS↓ |
| Ag+ | Cl- |
Precipitation of a white precipitate, insoluble in HNO 3, but soluble in ammonia NH 3 H 2 O: Ag + + Cl − → AgCl↓ |
| Fe2+ |
2) Potassium hexacyanoferrate (III) (red blood salt) K 3 |
1) Precipitation of a white precipitate that turns green in air: Fe 2+ + 2OH - \u003d Fe (OH) 2 ↓ 2) Precipitation of a blue precipitate (turnbull blue): K + + Fe 2+ + 3- = KFe↓ |
| Fe3+ |
2) Potassium hexacyanoferrate (II) (yellow blood salt) K 4 3) Rhodanide ion SCN − |
1) Precipitation of brown color: Fe 3+ + 3OH - \u003d Fe (OH) 3 ↓ 2) Precipitation of a blue precipitate (Prussian blue): K + + Fe 3+ + 4- = KFe↓ 3) The appearance of intense red (blood red) staining: Fe 3+ + 3SCN - = Fe(SCN) 3 |
| Al 3+ | Alkali (hydroxide amphoteric properties) |
Precipitation of a white precipitate of aluminum hydroxide when a small amount of alkali is added: OH - + Al 3+ \u003d Al (OH) 3 and its dissolution upon further addition: Al(OH) 3 + NaOH = Na |
| NH4+ | OH − , heating | Emission of gas with a pungent odor: NH 4 + + OH - \u003d NH 3 + H 2 O Blue wet litmus paper |
| H+ (acid environment) |
Indicators: − litmus − methyl orange |
Red staining |
Qualitative reactions to anions
| Anion | Impact or reagent | Reaction sign. Reaction equation |
| SO 4 2- | Ba 2+ |
Precipitation of a white precipitate, insoluble in acids: Ba 2+ + SO 4 2- \u003d BaSO 4 ↓ |
| NO 3 - |
1) Add H 2 SO 4 (conc.) and Cu, heat 2) A mixture of H 2 SO 4 + FeSO 4 |
1) Formation of a blue solution containing Cu 2+ ions, brown gas evolution (NO 2) 2) The appearance of the color of nitroso-iron sulfate (II) 2+. Violet to brown color (brown ring reaction) |
| PO 4 3- | Ag+ |
Precipitation of a light yellow precipitate in a neutral medium: 3Ag + + PO 4 3- = Ag 3 PO 4 ↓ |
| CrO 4 2- | Ba 2+ |
Precipitation of a yellow precipitate, insoluble in acetic acid, but soluble in HCl: Ba 2+ + CrO 4 2- = BaCrO 4 ↓ |
| S2- | Pb 2+ |
Black precipitation: Pb 2+ + S 2- = PbS↓ |
| CO 3 2- |
1) Precipitation of a white precipitate, soluble in acids: Ca 2+ + CO 3 2- \u003d CaCO 3 ↓ 2) Emission of a colorless gas ("boiling"), causing the lime water to become cloudy: CO 3 2- + 2H + = CO 2 + H 2 O |
|
| CO2 | Lime water Ca(OH) 2 |
Precipitation of a white precipitate and its dissolution upon further passage of CO 2: Ca(OH) 2 + CO 2 = CaCO 3 ↓ + H 2 O CaCO 3 + CO 2 + H 2 O \u003d Ca (HCO 3) 2 |
| SO 3 2- | H+ |
SO 2 gas evolution with a characteristic pungent odor (SO 2): 2H + + SO 3 2- \u003d H 2 O + SO 2 |
| F- | Ca2+ |
Precipitation of a white precipitate: Ca 2+ + 2F - = CaF 2 ↓ |
| Cl- | Ag+ |
Precipitation of a white cheesy precipitate, insoluble in HNO 3 but soluble in NH 3 H 2 O (conc.): Ag + + Cl - = AgCl↓ AgCl + 2(NH 3 H 2 O) =) Did not find an answer to your question? Look at here
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