Port Said International Schools
Better Education for Future Generations
Science Department
Grade: 11
Unit 4 Revision
Name: ………………………………………. Date: ……………………………………………………
Choose the correct answer:
1. The calcium Cyanamid reacts with water and (hydrogen – nitrogen – nitrogen
dioxide – ammonia) gas evolves. Egypt 2011
2. Carnallite is ………… Egypt 2010
a. Calcium chloride and calcium phosphate.
b. Calcium fluoride and calcium phosphate.
c. Potassium chloride and calcium chloride.
d. Potassium chloride and magnesium chloride.
3. On adding sodium hydroxide to copper sulphate, then heating the product, the color
of the formed precipitate is (blue – black – yellow – reddish brown). Egypt 2009
4. All the following compounds decompose by heat except (HNO3 – NaNO3 – Na2CO3
– NaHCO3). Egypt 2008
5. On the electrolysis of molten sodium hydride (sodium metal – sodium oxide –
hydrogen gas – water) will form at the anode. Egypt 2008
6. On adding sodium hydroxide solution to aluminum salt solution, we obtain …….
a. White greenish precipitate soluble in excess of ammonium hydroxide.
b. White color.
c. Yellow precipitate.
d. White greenish precipitate soluble in excess of sodium hydroxide.
Show by balanced chemical equations:
1. Starting with ammonium chloride, how can you prepare one of the most important
fertilizers which provide the soil with nitrogen and phosphorous element?
Egypt 2011
∆
2NH4Cl + Ca(OH)2 → CaCl2 + 2H2O + 2NH3
3NH3 + H3PO4 → (NH4)3PO4
2. The effect of water on sodium oxide. Egypt 2009
Na2O + H2O → 2NaOH
3. The effect of water on calcium carbide. Egypt 2009
CaCN2 + 3H2O →CaCO3 + 2NH3
4. The effect of water on magnesium nitride. Egypt 2009
Mg3N2 + 6H2O → 2NH3 + 3Mg (OH)2
5. Magnesium ribbon reacts with nitrogen at high temperature then water is added to
the product. Egypt 2008
∆
3Mg + N2 → Mg3N2
Mg3N2 + 6H2O → 3Mg (OH)2 + 2NH3
6. The effect of passing the ammonia gas and carbon dioxide on saturated aqueous
solution of sodium chloride. Egypt 2008
NH3 + CO2 + NaCl +H2O → NaHCO3 + NH4Cl
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Port Said International Schools
Better Education for Future Generations
Science Department
Grade: 11
Unit 4 Revision
How can you differentiate between each of the following? "Chemical equations"
1. Aluminum chloride solution and iron (3) chloride solution. Egypt 2010
AlCl3 + 3NaOH → 3NaCl + Al (OH)3 ↓ white ppt
Al (OH)3 + NaOH → NaAlO2 + 2H2O
FeCl3 + 3NaOH →Fe(OH)3 +3 NaCl
2. Copper (2) sulphate solution and iron (2) sulphate solution. Egypt 2010
CuSO4 + 2NaOH → Cu (OH)2 ↓ blue ppt +Na2SO4
∆
Cu (OH) 2 → CuO ↓ H2O
FeSO4 + 2NaOH → Na2SO4 + Fe (OH)2 ↓ (white ppt turns to greenish ppt).
3. Nitrate and nitrite salt. Egypt 2009
Add acidified potassium dichromate to both salts solutions. The color of the potassium
dichromate disappears in the case of the nitrite salt.
𝑐𝑜𝑛𝑐.
5KNO2 + 2KMnO4 + 3H2SO4 →
5KNO3 + K2SO4 + 2MnSO4 + 3H2O
4. Copper (2) sulphate and aluminum sulphate. Egypt 2008
CuSO4 + 2NaOH → Cu (OH) 2 ↓ blue ppt + Na2SO4
∆
Cu (OH) 2 → CuO ↓ H2O
AlCl3 + 3NaOH → 3NaCl + Al (OH)3 ↓ white ppt
Al (OH)3 + NaOH → NaAlO2 + 2H2O
Correct the underlined words:
1. When the atoms of the sodium are excited, they give golden yellow color, while the
cesium atom gives bluish violet. Egypt 2010
 Draw the apparatus used for the preparation of ammonia gas and write the balanced
chemical equation. Egypt 2010
The summary page 11
 Draw the apparatus used to prepare nitric acid in the laboratory.
o Write the chemical equation.
The summary page 14
o How can you differentiate practically between the diluted nitric acid the
concentrated nitric acid? Egypt 2008
∆ 𝑑𝑖𝑙
 3Cu + 8HNO3 → 3Cu(NO3)2 + 2NO + 4H2O. copper reacts with diluted nitric acid
to produce colorless gas (NO) that turns in to a reddish brown gas after a while
(NO)2.
𝑐𝑜𝑛.
 3Cu + 4HNO3 → 3Cu(NO3)2 + 2NO2 + 2H2O ↑. Copper reacts with concentrated
nitric acid to produce a reddish brown gas directly (NO)2
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Port Said International Schools
Better Education for Future Generations
Science Department
Grade: 11
Unit 4 Revision
Write the scientific explanation of the following:
1. Concentrated sulphuric acid is not used to dry ammonia gas. Egypt 2009
Because conc. Sulphuric acid reacts with sulphuric acid to produce ammonium sulphate
2. Nitrogen has many oxidation states. Egypt 2009
Because nitrogen can share with 3 electrons through covalent sharing or lose 5 electrons,
also nitrogen has positive oxidation numbers in its oxides due to the higher
electronegativity of oxygen
3. The weakness of the metallic bond between the 1st group elements.
Because these elements have one electron in the outer most level
4. Calcium Cyanamid is used as a fertilizer.
When calcium Cyanamid reacts with irrigation water it produces ammonia gas which is a
source of nitrogen for the soil
5. The alloy of bismuth, lead, cadmium and tin is used in making fuses.
Because they are characterized by low melting point
6. Nitric acid is a strong oxidizing agent.
Because oxygen gas evolved as a result of its thermal decomposition
7. Concentrated hydrochloric acid is used in detecting the ammonia gas.
Because ammonia gas combined with conc. Hydrochloric acid and produces white fumes
of ammonium chloride
𝑐𝑜𝑛.
NH3 + HCl → NH4Cl (white fumes)
What is the role of each of the following?
1. Calcium oxide in the preparation of ammonia gas. Egypt 2008
For drying the ammonia gas during its preparation in lab
2. Potassium super oxide in air filtration. Egypt 2008
Potassium super oxide reacts with carbon dioxide gas to produce oxygen gas.
What is meant by?
1. Representative elements. Egypt 2008
The elements of s and p blocks whose elements are characterized with the filling of all
energy levels except the highest level (the last level)
2. Allotropy.
The presence of an element in different forms, different in physical properties and similar
in chemical properties
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