chemical literacy - equations · 3. the skill of balancing equations an equation is a balance sheet...

Chemical Literacy 2.1

Created by

G.R. Marsden

Chemical Literacy - equations

HCl + Zn --> ZnCl2 + H2

Unbalanced?What do youmean I’munbalanced?

This package will teach you how to write conventional equations for thereactions you encounter. It follows from the first package that teaches youformulae. If you can do these, it will give your teacher confidence that you canhandle the really good experiments.


By Year 11 you should have learned this Page - It showsthe common chemical valencies for metals, non metals and radicals.There are three columns for metals, non metals and radicals. Ion charges are also included and are thesame as the valencies.. These you will use later. For the first assignments you will ignore the chargesand use only the valence numbers as shown by the headings. If the charge is missing, no ion forms.

VALENCE 1Sodium Na+ Fluorine F- Ammonium NH4+Potassium K+ Chlorine Cl- Hydroxide OH-Silver Ag+ Bromine Br- Nitrate NO3-Hydrogen H+ Iodine I- Bicarbonate HCO3-

Bisulphate HSO4-

VALENCE 2Magnesium Mg2+ Oxygen O2- Sulphate SO42-Calcium Ca2+ Sulphur S2- Carbonate CO32-Barium Ba2+Zinc Zn2+Lead Pb2+Copper II Cu2+Iron II Fe2+Tin II Sn2+Mercury II Hg2+

VALENCE 3Aluminium Al3+ Phosphate PO43-Iron III Fe3+

VALENCE 4Carbon CSilicon Si

VALENCE 5Nitrogen NPhosphorus P

One way to learn this

is to make up a card system

with the name on front and

symbol and valence on the

back. Shuffle the cards and

practise.


MORE ELEMENTS...In case you were feeling lonely, we thought you might like a few more. Notice that somebeasts have variable valence. It is all too common, particularly among non metals andtransition metals in the centre of the periodic table. The most common valence isshown first. Oh and don't take them as Gospel. For instance chlorine can have a valenceof 7. Of such is the price of freedom in our universe.....

ELEMENT SYMB TYPE VALENCE APPEARANCE ION OLD NAME (Metal?)

Aluminium Al M 3 Silver solid Al3+

Argon Ar NM 0 Colourless gasBarium Ba M 2 Silver solid Ba2+

Bromine Br NM 1 Brown liquid Br-

Calcium Ca M 2 Grey solid Ca2+

Carbon C NM 4 (2) Black solidChlorine Cl NM 1 Yellow-green gas Cl-

Chromium Cr M 3(2,6) Silver blue sol Cr3+

Cobalt Co M 2(3) Grey solid Co2+

Copper Cu M 2(1) Brown solid Cu2+ CuprumFluorine F NM 1 Green gas F-

Gold Au M 3(1) Yellow solid Au3+ AurumHelium He NM 0 Colourless gasHydrogen H NM 1 Colourless gas H+

Iodine I NM 1 Purple grey solid I-

Iron Fe M 3(2) Grey solid Fe3+ FerrumLead Pb M 2(4) Grey solid Pb2+ PlumbumLithium Li M 1 Grey solid Li+

Magnesium Mg M 2 Grey solid Mg2+

Manganese Mn M 2(3467) Grey solid Mn2+

Mercury Hg M 2(1) Grey liquid Hg2+ HydrogyrumNeon Ne NM 0 ColourlessgasNickel Ni M 2(3) Grey solid Ni2+

Nitrogen N NM 3(542) Colourless gasOxygen O NM 2 Colourless gas O2-

Phosphorus P NM 5(34) Brown solidPotassium K M 1 Grey solid K+ KaliumSilicon Si M 4 Grey solidSilver Ag M 1 Silver solid Ag+ ArgentumSodium Na M 1 Silver solid Na+ NatriumSulphur S NM 2(46) Yellow solidTin Sn M 4(2) Silver solid StannumTitanium Ti M 4(3) Silver solidTungsten W M 6(5432) Grey solid WolframUranium U M 6(543) Grey solidZinc Zn M 2 Grey solid Zn2+


THE RADICALS.....Radicals are complex particles which form when two or more atoms bond together to form a more stablespecies. During their initial formation, electrons are either gained from another chemical or lost, and soradicals are always charged..Because they are charged ions, radicals are found only......

Bonded ionically with other ions in crystals of ionic compounds.In solution or in the molten state where they are free.

1. The valence of a radical is the same as the charge2. Most radicals form the second part of a chemical formula. The exceptions to this are acetate and itsrelatives, and the ammonium radical.

Name Formula Name FormulaAmmonium NH4+ Acetate CH3COO-Carbonate CO32- Bicarbonate HCO3-

(hydrogen carbonate)Chlorate ClO3- Chlorite ClO2-Chromate CrO42- Dichromate Cr2O72-

(bichromate)Hydroxide OH- Hypochlorite ClO-Mercurous Hg22+ Nitrate NO3-Nitrite NO2- Oxalate C2O42-Hydrogen oxalate HC2O4- Perchlorate ClO4-Permanganate MnO4- Peroxide O22-Superoxide O2- Phosphate PO43-

Hydrogen phosphate HPO42-Dihydrogen phosphate H2PO4-

Sulfate SO42- Bisulfate HSO4-(hydrogen sulfate)

Bisulfide HS- Sulfite SO32-(hydrogen sulfide)Bisulfite HSO3-

NOTE.


1. The Skill of Counting AtomsIn order to balance chemical equations, we need to be able to count all the element atoms.

In chemical equations, you will find formulae such as these:

4Fe(HCO3)2The elements with no number underneath have one atom in the formula

The number 3 in the formula tell us that there are three oxygens inside the brackets

The number 2 multiplies everything inside the brackets only by 2

The number 4 tells us that there are 4 molecules of the chemical. It multiplies the wholeformula by 4 .

Element atom Calculation Total atoms

Fe 4 x 1 4H 4 x 1 x 2 8C 4 x 1 x 2 8O 4 x 3 x 2 24

☺☺☺☺☺ Set 1 Counting atomsCount the number of oxygen atoms in these terms found in balanced chemical equations:

1. 4Al2O3

2. KOH

3. 3NH4OH

4. 2Al2(SO4)3

5. 3Fe(NO3)3

6. 6NaHCO3

7. 5Cu(HSO4)2

8. 2(NH4)3PO4

9. Ca3(PO4)2

10. 4NaNO3


2. The Skill of Writing Word EquationsThere are many different families of reactions in chemistry. I will concentrate on those that you aremost likely to face.

a) Burning elements (same as combustion, oxidation )The element combines with oxygen forming the element oxide

eg. Combustion of magnesium

Magnesium + oxygen gas --> magnesium oxide

NB Some non metal oxides are unusual - carbon dioxide, sulfur dioxide, phosphorus pentoxide

b) Burning FuelsEach element in the fuel burns.

eg. Burning methane CH4 (This is the stuff that burns in the bunsens.)

Methane + oxygen gas --> carbon dioxide + water

c) Synthesis reactionsThis is where two elements get married to form a compound. The second element (the non metalbecomes the -ide word).

eg. Heating iron with sulfur

Iron + sulfur --> iron sulfide

d) Acid - metal reactionsNitric acid is a bit unusual and highly dangerous as it emits nitrogen dioxide gas. We tend toconcentrate on hydrochloric and sulfuric acid, which form chloride and sulfate salts.

Acid + metal --> metal salt + hydrogen gas

eg Sulfuric acid + zinc --> zinc sulfate + hydrogen gas

e) Acid-base reactions (neutralisations)In neutralisations, a salt and water are produced. These are such fun reactions that we do several:

Acid + metal oxide --> metal salt + waterAcid + metal hydroxide --> metal salt + waterAcid + metal carbonate --> metal salt + carbon dioxide + waterAcid + metal bicarbonate --> metal salt + carbon dioxide + waterAcid + metal sulfide --> metal salt + hydrogen sulfide + water


f) Decomposition ReactionsWhen you heat some chemicals, they break up (decompose) into simpler chemicals. It will happen tome one day.

Δeg Magnesium carbonate --> magnesium oxide + carbon dioxide

ΔMagnesium hydroxide --> magnesium oxide + water

☺☺☺☺☺ Set 2 Writing word equationsWrite word equations for the following:

1. Burning calcium2. Oxidation of lead3. Combustion of iron (steel wool)4. Combustion of carbon (coal or coke)5. Combustion of sulfur6. Burning hydrogen7. Burning ethane fuel C2H68. Burning ethanol fuel C2H5OH (Ethanol is the main chemical in methylated spirit).9. Heating iron in chlorine gas10. Heating copper in chlorine gas11. Heating sodium in chlorine gas12. Heating sodium with iodine13. Hydrochloric acid + zinc14. Hydrochloric acid + iron15. Sulfuric acid + calcium16. Sulfuric acid + magnesium17. Hydrochloric acid + sodium18. Hydrochloric acid + magnesium oxide19. Hydrochloric acid + calcium hydroxide20. Hydrochloric acid + sodium hydroxide21. Hydrochloric acid + sodium carbonate22. Hydrochloric acid + calcium carbonate23. Hydrochloric acid + sodium bicarbonate24. Sulfuric acid + magnesium oxide25. Sulfuric acid + calcium hydroxide26. Sulfuric acid + sodium hydroxide27. Sulfuric acid + sodium carbonate28. Sulfuric acid + calcium carbonate29. Sulfuric acid + sodium bicarbonate30. Calcium carbonate heated31. Nitric acid + calcium carbonate32. Calcium hydroxide heated33. Nitric acid + copper carbonate34. Nitric acid + copper oxide

You may need extrahelp with this one!


3. The Skill of Balancing EquationsAn equation is a balance sheet with the things reacting on the left hand side of the reaction and thethings being formed on the right. From the law of conservation of mass, we know that atoms cannotbe created or destroyed in a chemical reaction. It follows that the total numbers of atoms must be thesame on both sides of the equation for each element. The atoms in your bodies last for billions ofyears. The only ways to change them are in nuclear reactions or by fusion of atomic nuclei in thecores of stars.

Equations are balanced by taking each element in turn and adjusting the numbers in front of eachchemical until the atom numbers total correctly.

Example Balance Fe + O2 —> FeO Fe 1 1 OK O 2 1

Oxygens do not balance so we double the FeO to balance the oxygens

Fe + O2 —> 2FeO Fe 1 2

Now the irons are unbalanced. So we double the Fe

2Fe + O2 —> 2FeOFe 2 2 OKO 2 2 OK

☺☺☺☺☺ Set 3 Balancing Some Synthesis ReactionsSynthesis reactions involve the combination of simple chemicals to form a more complex chemical.Notice that a lot of gases are diatomic in nature. Remember that a formula cannot be changed. Nevertouch the numbers at the bottom. The only thing that you can manipulate is the numbers of eachformula. These numbers go in front of each chemical and are multipliers.Balance the following :-

1. Al + O2 —> Al2O3

2. Cu + O2 —> CuO

3. Al + S —> Al2S3

4. Na + O2 —> Na2O

5. Fe + Cl2 —> FeCl36. H2O + CO2 —> C6H12O6 + O2

7. Fe + O2 —> Fe2O3

8. N2 + H2 --> NH3

9. H2 + O2 --> H2O

10. CO + O2 --> CO2

Be patient with these.Do them in steps.Don’t freak out!


☺☺☺☺☺ Set 4 Administering our Caring Chemical Skills to the Unbalanced. Balance the following if you dare face the demons of the mind :-

1. Na + H2O -> NaOH + H2

2. HCl + Al -> AlCl3 + H2

3. P2O5 + H2O -> H3PO4

4. NaHCO3 -> Na2CO3 + H2O + CO2

5. HNO3 + CaCO3 -> Ca(NO3)2 + CO2 + H2O

6. H2SO4 + Al(OH)3 -> Al2(SO4)3 + H2O

7. Al + H2O -> Al(OH)3 + H2

8. HCl + Ca(OH)2 -> CaCl2 + H2O

9. Mg + H2O -> Mg(OH)2 + H2

10.H3PO4 + CaCO3 -> Ca3(PO4)2 + CO2 + H2O

4. The Skill of Equation WritingIn these reactions, elements are combining to form a compound. These are some synthesis reactions,where simple things combine to form compounds.

Metal + non metal —> metal non metalide Metal + oxygen —> metal oxide Non metal + oxygen —> non metal oxide

Steps1. Write the word equation for the reaction using the above as a guide2. Use valence rules to write formulae underneath for each chemical in the word equation3. Remember gases H2 Cl2 O2 CO24. Balance the equation.

eg Write a balanced equation for burning magnesium.We use the second equation as a guide. Note that oxygen gas is diatomic.........O2

Magnesium + oxygen gas --> magnesium oxide

Mg + O2 --> Mg2 O2 .............VALENCIES

Mg + O2 --> Mg1 O1 .............Cancelling numbers at top

Mg + O2 --> Mg1O1 ............crossing over to obtain formula

Mg + O2 --> 2MgO ............balancing oxygens

2Mg + O2 --> 2MgO ............balancing magnesiums


☺☺☺☺☺ Set 5 Writing Synthesis Symbol EquationsWrite formula equations for each of the following1. Combustion of sodium2. Combustion of carbon3. Combustion of sulphur (sulphur assumes +4 oxidation state)4. Rusting of tin (tin valence +2)5. Rusting of iron (iron valence +3)6. Heating aluminium plus sulphur7. Heating tin and sulphur (tin +2)8. Heating copper with chlorine9. Heating aluminium with chlorine10. Oxidation of silver

Burning CompoundsWhen something burns, each element forms an oxide, the only exception being oxygen itself. Oftenthe things we burn contain more than one non metals. This little table shows the oxides that somenon metals form :-

Non metal Oxide Name

H H2O waterC CO2 carbon dioxideS SO2 sulphur dioxideN NO2 nitrogen dioxide

For example, if you burn methane CH4 , the word equation is:-

Methane + oxygen --> carbon + watergas dioxide

☺☺☺☺☺ Set 6 Writing Combustion Symbol EquationsWrite word and symbol equations for the combustion of the following compounds :-1. methane CH42. ethane C2H63. propane C3H84. butane C4H105. ethyne (acetylene) C2H26. ammonia NH37. hydrogen sulphide H2S8. ethanol C2H5OH9. methanol CH3OH10. octane C8H18


☺☺☺☺☺ Set 7 Writing Symbol Equations for Acid ReactionsAcid + metal --> metal salt + hydrogen gas

eg Sulfuric acid + zinc --> zinc sulfate + hydrogen gas

In neutralisations, a salt and water are produced :

Acid + metal oxide --> metal salt + waterAcid + metal hydroxide --> metal salt + waterAcid + metal carbonate --> metal salt + carbon dioxide + waterAcid + metal bicarbonate --> metal salt + carbon dioxide + water

eg Nitric acid + sodium carbonate --> sodium nitrate + carbon dioxide + waterHydrochloric acid + potassium hydroxide --> potassium chloride + water

Write word and symbol equations for these meaningful acidifying learning experiences:

1. Sulfuric acid + copper oxide

2. Hydrochloric acid + magnesium oxide

3. Nitric acid + calcium oxide

4. Hydrochloric acid + sodium hydroxide

5. Nitric acid + potassium hydroxide

6. Sulfuric acid + calcium hydroxide

7. Hydrochloric acid + zinc

8. Hydrochloric acid + calcium

9. Sulfuric acid + aluminium

10. Sulfuric acid + calcium carbonate

11. Hydrochloric acid + sodium carbonate

12. Nitric acid + potassium carbonate

13. Hydrochloric acid + sodium bicarbonate

14. Nitric acid + potassium bicarbonate

15. Sulfuric acid + calcium bicarbonate


☺☺☺☺☺ Set 8 Writing Symbol Equations for Decomposition Reactions

A number of chemicals break up into simpler chemicals when they are heated strongly. Thesereactions are usually performed in a crucible rather than a test tube.

1. Heating mercury (2) oxide

2. Heating calcium carbonate forming carbon dioxide gas

3. Heating ammonium carbonate forming ammonia NH3 and two other chemicals in gas form

4. Heating magnesium carbonate

5. Heating calcium hydroxide forming calcium oxide as one product

6. Heating copper carbonate

7. Heating silver oxide

8. Heating copper nitrate forming NO2 and O2 as well as copper oxide

9. Heating sodium bicarbonate forming sodium carbonate and two other common chemicals

10. Heating magnesium hydroxide

Writing Equations for Dissolving Ionic CompoundsWhen ionic compounds dissolve in water, they break up into a positive ion and a negative ion. Thesolution formed is a mixture of two ions. Ionic compounds include acids, alkalis and salts.

eg 1. Dissolving sodium chloride in water

Sodium chloride solid --> sodium ions + chloride ions

NaCl(S) --> Na+(AQ) + Cl-(AQ)

Notice that the first ion is positive and the second ion negative. The number of charges at the top ofthe ion is the same as its valence.

eg 2. Dissolving magnesium chloride in water

Magnesium chloride solid --> sodium ions + chloride ions

MgCl2(S) --> Mg2+(AQ) + 2Cl-(AQ)

eg 3. Dissolving aluminium sulfate in water

Aluminium sulfate solid --> aluminium ions + sulfate ions

Al2(SO4)3(S) --> 2Al3+(AQ) + 3SO4

2-(AQ)

Note the meanings of these subscripts:

(AQ) = dissolved in water (S) = solid (G) = gas (L) = liquid


☺☺☺☺☺ Set 9 Dissolving Ionic Compounds in waterWrite word and symbol equations for dissolving these acids, alkalis or soluble salts in water:

1.Hydrochloric acid gas HCl(G) in water forming hydrochloric acid solution

2. Concentrated sulphuric acid H2SO4(L) in water. (A very dangerous exothermic reaction).

3. Dissolving the solid strong alkali sodium hydroxide in water

4. Dissolving the weak solid alkali sodium carbonate in water

5. Dissolving the weak solid alkali potassium carbonate in water

6. Dissolving the salt magnesium sulfate in water

7. Dissolving the salt potassium nitrate in water

8. Dissolving the salt copper chloride in water

9. Dissolving the salt aluminium chloride in water

10. Dissolving the salt ammonium sulfate in water

Writing Equations for Precipitation ReactionsPrecipitation reactions are the last to be mentioned in the junior syllabus. We have dealt with theothers in turn. You may have noticed that, in the last set above, we are starting to write ionic

equations, the final skill of the chemist.

Precipitations occur when two solutions of ionic compounds are mixed. Each solution contains two

ions. A positive ion from one solution combines with a negative ion from the other solution to form

a gluggy suspension of solid in water. The solid settles under gravity to form a precipitate.

Working out which two ions are forming the precipitate is a problem. So I will give you 2 rules that

may help:

All sodium, ammonium, potassium and hydrogen compounds are soluble.

Most carbonates and hydroxides are insoluble except for the ions in rule 1.

eg. Write an equation for adding sodium carbonate solution to copper sulfate solution.

We swap the ions over.

Rule 1 implies that sodium sulfate is soluble. Rule 2 implies that copper carbonate is insoluble. The

equations are the reverse of the dissolving reactions in set 9

copper ions + carbonate ions --> copper carbonate precipitate

Cu2+(AQ) + CO3

2- --> CuCO3(S)


☺☺☺☺☺ Set 10 Writing Precipitation ReactionsWrite word and symbol equations for these precipitation reactions:

1. Precipitation of silver chloride from hydrochloric acid plus silver nitrate solution.

2. Precipitation of lead sulphate from lead nitrate solution plus potassium sulfate solution.

3. Precipitation of calcium hydroxide from calcium nitrate solution plus sodium hydroxide solution.

4. Precipitation of lead hydroxide from lead nitrate solution plus potassium hydroxide solution.

5. Precipitation of lead chloride from lead nitrate solution plus sodium chloride solution.

6. Copper chloride solution + sodium hydroxide solution.

7. Silver nitrate solution + potassium carbonate solution.

8. Lead nitrate solution + sodium carbonate solution.

9. Aluminium chloride solution + sodium hydroxide solution.

10. Magnesium sulfate solution + sodium hydroxide solution.


Solutions Set 11) 12 2) 1 3) 3 4) 24 5) 27 6) 18 7) 40 8) 8 9) 8 10) 12

Solutions Set 21. calcium + oxygen gas --> calcium oxide2. lead + oxygen gas --> lead oxide3. iron + oxygen gas --> iron oxide4. carbon + oxygen gas --> carbon dioxide5. sulfur + oxygen gas --> sulfur dioxide6. hydrogen + oxygen gas --> hydrogen oxide (water)7. ethane fuel + oxygen gas --> carbon dioxide + water8. ethanol fuel + oxygen gas --> carbon dioxide + water9. iron + chlorine gas --> iron chloride10. copper + chlorine gas --> copper chloride11. sodium + chlorine gas --> sodium chloride12. sodium + iodine --> sodium iodide13. hydrochloric acid + zinc --> zinc chloride + hydrogen gas14. hydrochloric acid + iron --> iron chloride + hydrogen gas15. sulfuric acid + calcium --> calcium sulfate + hydrogen gas16. sulfuric acid + magnesium --> magnesium sulfate + hydrogen gas17. hydrochloric acid + sodium --> sodium chloride + hydrogen gas18. hydrochloric acid + magnesium oxide --> magnesium chloride + water19. hydrochloric acid + calcium hydroxide --> calcium chloride + water20. hydrochloric acid + sodium hydroxide --> sodium chloride + water21. hydrochloric acid + sodium carbonate --> sodium chloride + carbon dioxide + water22. hydrochloric acid + calcium carbonate --> calcium chloride + carbon dioxide + water23. hydrochloric acid + sodium bicarbonate --> sodium chloride + carbon dioxide + water24. sulfuric acid + magnesium oxide --> magnesium sulfate + water25. sulfuric acid + calcium hydroxide --> calcium sulfate + water26. sulfuric acid + sodium hydroxide --> sodium sulfate + water27. sulfuric acid + sodium carbonate --> sodium sulfate + carbon dioxide + water28. sulfuric acid + calcium carbonate --> calcium sulfate + carbon dioxide + water29. sulfuric acid + sodium bicarbonate --> sodium sulfate + carbon dioxide + water

Δ30. calcium carbonate --> calcium oxide + carbon dioxide31. nitric acid + calcium carbonate --> calcium nitrate + carbon dioxide + water

Δ32. calcium hydroxide --> calcium oxide + water33. nitric acid + copper carbonate --> copper nitrate + carbon dioxide + water34. nitric acid + copper oxide --> copper nitrate + water


Solutions Set 31. 4Al + 3O2 —> 2Al2O3

2. 2Cu + O2 —> 2CuO

3. 2Al + 3S —> Al2S3

4. 4Na + O2 —> 2Na2O

5. 2Fe + 3Cl2 —> 2FeCl36. 6H2O + 6CO2 —> C6H12O6 + 6O2

7. 4Fe + 3O2 —> 2Fe2O3

8. N2 + 3H2 --> 2NH3

9. 2H2 + O2 --> 2H2O

10. 2CO + O2 --> 2CO2

Solutions Set 41. 2Na + 2H2O -> 2NaOH + H2

2. 6HCl + 2Al -> 2AlCl3 + 3H2

3. P2O5 + 3H2O -> 2H3PO4

4. 2NaHCO3 -> Na2CO3 + H2O + CO2

5. 2HNO3 + CaCO3 -> Ca(NO3)2 + CO2 + H2O

6. 3H2SO4 + 2Al(OH)3 -> Al2(SO4)3 + 6H2O

7. 2Al + 6H2O -> 2Al(OH)3 + 3H2

8. 2HCl + Ca(OH)2 -> CaCl2 + 2H2O

9. Mg + 2H2O -> Mg(OH)2 + H2

10.2H3PO4 + 3CaCO3 -> Ca3(PO4)2 + 3CO2 + 3H2O

Solutions Set 51. 4Na + O2 —> 2Na2O

2. C + O2 —> CO2

3. S + O2 —> SO2

4. 2Sn + O2 —>2 SnO

5. 4Fe + 3O2 —> 2Fe2O3

6. 2Al + 3S —>Al2S3

7. Sn + S —> SnS

8. Cu + Cl2 —> CuCl29. 2Al + 3Cl2 —> 2AlCl310. 4Ag + O2 —> 2Ag2O

Solutions Set 61. CH4 + 2O2 —> CO2 + 2H2O

2. 2C2H6 + 7O2 —> 4CO2 + 6H2O

3. C3H8 + 5O2 —> 3CO2 + 4H2O

4. 2C4H10 + 13O2 —> 8CO2 + 10H2O

5. 2C2H2 + 5O2 —> 4CO2 + 2H2O

6. 4NH3 + 7O2 —> 4NO2 + 6H2O

7. 2H2S + 3O2 —> 2H2O + 2SO2

8. C2H5OH + 3O2 —> 2CO2 + 3H2O

9. 2CH3OH + 3O2 —> 2CO2 + 4H2O

10.2C8H18 + 25O2 —> 16CO2 + 18H2O


Solutions Set 71. Sulfuric acid + copper oxide --> copper sulfate + water

H2SO4 + CuO --> CuSO4 + H2O

2. Hydrochloric acid + magnesium oxide --> magnesium chloride + water

2HCl + MgO --> MgCl2 + H2O

3. Nitric acid + calcium oxide --> calcium nitrate + water

2HNO3 + CaO --> Ca(NO3)2 + H2O

4. Hydrochloric acid + sodium hydroxide --> sodium chloride + water

HCl + NaOH --> NaCl + H2O

5. Nitric acid + potassium hydroxide --> potassium nitrate + water

HNO3 + KOH --> KNO3 + H2O

6. Sulfuric acid + calcium hydroxide --> calcium sulfate + water

H2SO4 + Ca(OH)2 --> CaSO4 + 2H2O

7. Hydrochloric acid + zinc --> zinc chloride + hydrogen

2HCl + Zn --> ZnCl2 + H2

8. Hydrochloric acid + calcium --> calcium chloride + hydrogen

2HCl + Ca --> CaCl2 + H2

9. Sulfuric acid + aluminium --> aluminiun sulfate + hydrogen

3H2SO4 + 2Al --> 2Al2(SO4)3 + 3H2

10. Sulfuric acid + calcium carbonate --> calcium sulfate + carbon dioxide + water

H2SO4 + CaCO3 --> CaSO4 + CO2 + H2O

11. Hydrochloric acid + sodium carbonate --> sodium chloride + carbon dioxide + water

2HCl + Na2CO3 --> 2NaCl + CO2 + H2O

12. Nitric acid + potassium carbonate --> potassium nitrate + carbon dioxide + water

2HNO3 + K2CO3 --> 2KNO3 + CO2 + H2O

13. Hydrochloric acid + sodium bicarbonate --> sodium chloride + carbon dioxide + water

HCl + NaHCO3 --> NaCl + CO2 + H2O

14. Nitric acid + potassium bicarbonate --> potassium nitrate + carbon dioxide + water

HNO3 + KHCO3 --> KNO3 + CO2 + H2O

15. Sulfuric acid + calcium bicarbonate --> calcium sulfate + carbon dioxide + water

H2SO4 + Ca(HCO3)2 --> CaSO4 + 2CO2 + 2H2O


Solutions Set 81. mercury (2) oxide --> mercury + oxygen gas

Δ 2HgO --> 2Hg + O2

2. calcium carbonate --> calcium oxide + carbon dioxide gas

ΔCaCO3 --> CaO + CO2

3. ammonium carbonate --> ammonia + carbon dioxide + waterΔ

(NH4)2CO3 --> 2NH3 + CO2 + H2O

4. magnesium carbonate --> magnesium oxide + carbon dioxide

Δ MgCO3 --> MgO + CO2

5. calcium hydroxide --> calcium oxide + water

Δ Ca(OH)2 --> CaO + H2O

6. copper carbonate --> copper oxide + water

Δ CuCO3 --> CuO + CO2

7. silver oxide --> silver + oxygen gas

Δ 2Ag2O --> 4Ag + O2

8. copper nitrate --> copper oxide + nitrogen dioxide + oxygen gas

Δ 2Cu(NO3)2 --> 2CuO + 4NO2 + O2

9. sodium bicarbonate --> sodium carbonate + carbon dioxide + water

Δ 2NaHCO3 --> Na2CO3 + CO2 + H2O

10. magnesium hydroxide --> magnesium oxide + water

Δ Mg(OH)2 --> MgO + H2O


Solutions Set 91.Hydrochloric acid gas --> hydrogen ions + chloride ions

HCl(G) --> H+(AQ) + Cl(AQ)

2. Sulphuric acid --> hydrogen ions + sulfate ions

H2SO4(L) --> 2H+(AQ) + SO4

2-(AQ)

3. Sodium hydroxide --> sodium ions + hydroxide ions

NaOH(S) --> Na+(AQ) + OH-

(AQ)

4. Sodium carbonate --> sodium ions + carbonate ions

Na2CO3(S) --> 2Na+(AQ) + CO3

2-(AQ)

5. Potassium carbonate --> potassium ions + carbonate ions

K2CO3(S) --> 2K+(AQ) + CO3

2-(AQ)

6. Magnesium sulfate --> magnesium ions + sulfate ions

MgSO4(S) --> Mg2+(AQ) + SO4

2-(AQ)

7. Potassium nitrate --> potassium ions + nitrate ions

KNO3(S) --> K+(AQ) + NO3

-(AQ)

8. Copper chloride --> copper ion + chloride ions

CuCl2(S) --> Cu2+(AQ) + 2Cl-(AQ)

9. Aluminium chloride --> aluminium ion + chloride ions

AlCl3(S) --> Al3+(AQ) + 3Cl-(AQ)

10. Ammonium sulfate --> ammonium ions + sulfate ion

(NH4)2SO4(S) --> 2NH4(AQ)+ + SO4

2-(AQ)


Solutions Set 10

1. Silver ions + chloride ions --> silver chloride precipitateAg+

(AQ) + Cl-(AQ) --> AgCl(S)

2. Lead ions + sulfate ions --> lead sulphate precipitatePb2+

(AQ) + SO42-

(AQ) --> PbSO4(S)

3. Calcium ions + hydroxide ions --> calcium hydroxide precipitateCa2+

(AQ) + 2OH-(AQ) --> Ca(OH)2(S)

4. Lead ions + hydroxide ions --> lead hydroxide precipitatePb2+

(AQ) + 2OH-

(AQ) --> Pb(OH)2(S)

5. Lead ions + chloride ions --> lead chloride precipitatePb2+

(AQ) + 2Cl-(AQ) --> PbCl2(S)

6. Copper ions + hydroxide ions --> copper hydroxide precipitateCu2+

(AQ) + 2OH-(AQ) --> Cu(OH)2(S)

7. Silver ions + carbonate ions --> silver carbonate precipitate2Ag+

(AQ) + CO3

2--(AQ) --> Ag2CO3(S)

8. Lead ions + carbonate ions --> lead carbonate precipitatePb2+

(AQ) + CO32-

(AQ) --> PbCO3(S)

9. Aluminium ions + hydroxide ions --> aluminium hydroxide precipitate.Al3+

(AQ) + 3OH-

(AQ) --> Al(OH)3(S)

10. Magnesium ions + hydroxide ions --> magnesium hydroxide precipitateMg2+

(AQ) + 2OH-

(AQ) --> Mg(OH)2(S)


Writing word equations and balancing equationsSkill Test

NameYou are required to complete these word equations

1.Magnesium + oxygen gas -->

2.Calcium + oxygen gas -->

3. Methane (CH4) + oxygen gas -->

4. Carbon + oxygen gas -->

5. Hydrochloric acid + zinc -->

6. Sulfuric acid + magnesium -->

7. Hydrochloric acid + calcium oxide -->

8. Nitric acid + sodium hydroxide -->

9. Hydrochloric acid + calcium carbonate -->

10.Sulfuric acid + magnesium hydroxide -->

Balance these symbol equations. Do these in pencil first then go over in ink.

11 . HCl + Mg --> MgCl2 + H2

12. HCl + Na --> NaCl + H2

13. HCl + Na2CO3 --> NaCl + CO2 + H2O

14. Al + O2 --> Al2O3

15. P + O2 --> P2O5

16. P2O5 + H2O ---> H3PO4

17. C2H2 + O2 ---> CO2 + H2O

18. HCl + Al --> AlCl3 + H2

19. NO + O2 ---> NO2

20. H3PO4 + NH4OH --> (NH4)3PO4 + H2O


Writing symbol equations Skill TestName

You are required to complete these word equations and write a balanced symbol equation

1. Magnesium + oxygen gas -->

2. Sodium + oxygen gas -->

Δ3. Calcium carbonate -->

4. Hydrogen gas + oxygen gas -->

5. Hydrochloric acid + zinc -->


6. Sulfuric acid + magnesium oxide -->

7. Hydrochloric acid + calcium carbonate -->

8. Nitric acid + potassium hydroxide -->

9. Dissolving magnesium sulphate crystals in water

10. Precipitation of lead chloride from its ions


has mastered the skillof writing word equations

Grade

has mastered the skillof writing symbol equations

Grade

chemical literacy - equations · 3. the skill of balancing equations an equation is a balance sheet...

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