Physics & Chemistry 3 ESO Unit 1: Scientific method and measurement. Exercises

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1 1.- Express these quantities in SI units: Unit 1: Scientific method and measurement Exercises 1. Earth radius: 6,37 Mm (m) 2. Volume of a drop of water: 0,05 ml (m 3 ) 3. Mass of an ant: 0,5 mg (kg) 4. Spain area: km 2 (m 2 ) 5. Madrid area: ha (m 2 ) 6. Liver cell: 200 µm (m) 7. Radius of Hydrogen atom: 5 nm (m) 8. Energy of LHC collisions: 4,5 Tev (ev) 9. Internet connection: 180 Gbytes/h (bytes/s) 10. Density of aluminium: 2,7 g/cm 3 (kg/m 3 ) 11. Speed of light: 1080 Gm/h (m/s) 12. Formula 1 speed record: 413 km/h (m/s) 13. Speed limit UK: 70 miles/h (m/s) 14. Water viscosity: 1 g/cm.s (kg/m.s) 15. Madrid annual rainfall: 420 l/m 2 (m) 2.- Convert these quantities using the units in brackets g/cm 3 (kg/m 3 ) cm (km) cm 3 (m 3 ) 4. 0,00064 kg.m/s (g.cm/s) cg (kg) t/h (kg/s) µm (m) m 3 /h (cm 3 /s) 9. 0,0057 km (cm) MHertz (Hertz) m 2 (cm 2 ) 12. 0,06 litros (ml) 13. 0,0002 g/cm 2 (kg/m 2 ) m/s (km/h) t/m 2 (kg/cm 2 ) 3.- Find the correct value with the suitable number of significant figures 1. Volume of a room which has 4,52 m x 5,75 x 2,55 m 2. Total mass of three books which have 2520 g, 2675 g, 1530 g 3. Density of a steel esphere 35,5 g and 4,5 cm 3 4. Speed of a car which travels m in 45 minutes 5. Area of a sheet of paper which has 295 mm x 210 mm 4.- Express these quantities with scientific notation 1. Earth-Sun distance: m 2. Proton radius: 0, m 3. Electron charge: 0, C 4. Universe age: years 5. Earth mass: kg

2 Unit 2: Matter and kinetic theory Exercises 1.- A pond is 8 metres long, 4 metres wide and 50 cm deep. When we pour alcohol in it, the pond contains 12.6 tons of liquid. Find the density of alcohol. How much water can we pour in it?. How much mercury? Densities (g / cm 3 ): water: 1; mercury: 13,6 Sol: 788 kg.m -3 ; 16 tons; 218 tons 2.- The sides of a room are 8 and 5 metres and its height is 3,5 metres Find the mass of air contained in this room, if density of air is 1.3 g / l. Find the volumes of water and mercury with the same mass. Densities (g / cm 3 ): water: 1; mercury: 13,6 Sol: 182 kg; 140 tons; 1904 tons 3.- A cardboard box is 50 cm high and its sides are 1 metre long. Find the density of alcohol, if the mass of the box filled with alcohol is 395 kg. Find the mass of the air contained in this box supposing that the density of air is g/cm 3 Sol:790 kg.m -3 ; 4.- A glass bottle of 75 cl is filled with alcohol. Find the mass of alcohol, if the density of alcohol is 0.75 g/ml. Find the volume occupied by the same amount of mass of carbon dioxide or mercury. Densities: Carbon dioxide: 2 g / l; mercury: 13.6 g/cm 3 Sol: 592 g; 296 l; 43.5 cm We have filled a balloon with half a litre of air at 25º C. Then we place this balloon on a heater. Find the volume of the balloon at 35º, 50º and 65º C Sol: 517, 542 & 567 ml 6.- Imagine a syringe filled with 50 ml of nitrogen at 1 at. Find the pressure of the nitrogen contained in the syringe when we reduce the volume to 35 ml and 15 ml Sol: 1.43 at; 3.3 at 7.- A pressure cooker can work at the pressure of 1.1 or 1.2 at. Find the temperature of the water vapour contained in the pressure cooker when we heat a meal at these pressures Sol: 137º C; 174 º C 8.- We fill a tyre with air getting a pressure of 2.23 atmospheres at 25º C. Then the car starts to move and the tyres become hot. Find the pressure of the tyres at 50º C and 75º C Sol: 2,41 at; 2,6 at 9.- A 1000 litre-balloon is filled with helium at room temperature (25º C) and 1 at. Then it rises up and arrives to m high. Find the volume of the balloon: a) at m high, where pressure is 0,2 at and temperature is 20º C b) at m high, where pressure is 0,01 at and temperature is - 60º C c) at m high, where pressure is 0,001 and temperature is 10º C 10.- A bubble of air rises up from a submarine which is placed at 500 m of depth. Calculate its volume when it reaches to the surface of the sea at 15º C and 1 at, if it had 1 cm 3 of volume at 7 at of pressure and 10º C 11. Plot the heating graph of ethanol from 200 K to 400 K. Melting point of alcohol is and its boiling point is 79 º C

3 Unit 3: Mixtures & solutions Exercises 1.- A commercial disinfectant is a solution prepared solving 3 g of hydrogen peroxide in 99 g of water. Find its concentration expressed in grams per litre. The density of the solution is 1010 g.cm A standard hydrochloric solution is 35 % and its density is 1,19 g/ ml. Calculate its concentration expressed in grams per litre. How many mililitres of solution do you need to get 15 grams of hydrochloric acid? 3.- A standard solution of nitric acid is 69 % and its density is 1,41 grams per mililitre. Calculate its concentration expressed in grams per liter. How many mililitres do you need to get 60 grams of nitric acid. Calculate the mass of nitric acid in 100 mililitres of solution. 4.- We solve 15 g of sugar in 60 g water, getting a solution volume equal to 65 ml. Calculate the concentration of the solution expressed in mass percentage and grams per litre. Find the solution density. Calculate the mass of sugar found in 15 ml of solution. What is the volume of solution which contains 2 g of sugar? 5.- A solution of alt in water has 30 grams of salt per litre. Calculate tha amount of salt contained in a 200 cubic centimetre glass of solution. How many millilitres of solution do we need to get half a kilogram of salt?

4 Unit 5: Inorganic Nomenclature 1.- Write the formula or give the name of the following halides or hydrides: a) Aluminium chloride b) Calcium fluoride c) Rubidium bromide d) Mercury (II) hydride e) Tin (II) iodide k) PBr 5 l) CCl 4 m) HF n) NH 3 o) CoI 2 f) Ammonium chloride p) MgF 2 g) Palladium (IV) iodide h) Antimony pentabromide q) PtBr 4 r) FeH 2 i) Silane s) KCl j) Sulphur hexafluoride t) CdI Write the formula or give the name of the following oxides or sulphides: a) Diboron trioxide b) Diphosphorus pentasulphide c) Diantimony trioxide d) Selenium dioxide e) Carbon monoxide f) Titanium (IV) oxide g) Strontium oxide h) Ammonium sulphide i) Potassium selenide j) Magnesium telluride k) As 2 O 5 l) Cl 2 O 7 m) TeO 3 n) SiO 2 o) N 2 O 4 p) BaO q) Rb 2 O r) CrO 3 s) MnO 2 t) Pb 3 O Write the formula or give the name of the following ternary substances: a) Beryllium hydroxide b) Nitric acid c) Lithium chlorate d) Tin (II) hydroxide e) Sodium hypochlorite f) Silver carbonate g) Calcium phosphate h) Barium hydroxide i) Ammonium perchlorate j) Nitrous acid k) ZnSO 4 l) Co(OH) 3 m) H 2 SO 2 n) KClO 2 o) Pt(OH) 4 p) Na 3 PO 4 q) HgClO 3 r) H 2 CO 3 s) CuOH t) (NH 4 ) 2 SO 3

5 Unit 5: Inorganic Nomenclature 4.- Write the formula or give the name of the following chemical substances: a) Potassium fluoride k) FeO b) Nickel (II) oxide l) HgCl 2 c) Silver nitrate m) PF 3 d) Sulphur trioxide n) N 2 O 5 e) Barium hydroxide o) MgBr 2 f) Caesium hydride p) Cu(OH) 2 g) Aluminium hydroxide q) SiH 4 h) Hydroiodic acid r) B(OH) 3 i) Rubidium sulphide s) NH 3 j) Diarsenic trioxide t) HClO 5.- Write the formula of these chemical substances: a) Beryllium chloride b) Lithium oxide c) Magnesium hydride d) Boron trifluoride e) Tin (II) hydroxide f) Clorous acid g) Sodium carbonate h) Iron (II) sulphate i) Lead (IV) oxide j) Mercury dibromide k) Rubidium iodide l) Sulphur hexafluoride m) Potassium perclorate n) Zinc oxide o) Platinum tetrachloride p) Nitric acid q) Silver oxide r) Stibane s) Calcium hydroxide t) Hydrocloric acid 6.- Give the name of the following chemical substances: a) PH 3 b) CoO c) SrH 2 d) CF 4 e) Pt(OH) 2 f) H 2 SO 2 g) NaNO 2 h) Ca(ClO 3 ) 2 i) AgI j) PdO 2 k) Al(OH) 3 l) BaBr 2 m) HlO 4 n) Au 2 O o) CdCl 2 p) H 2 S q) MgCO 3 r) N 2 O 4 s) CuI 2 t) H 2 O 2

6 Unit 5: Inorganic Nomenclature 7.- Write the formula of the following chemical substances: a) Calcium chloride b) Potassium sulphate c) Copper (II) hydride d) Boron trifluoride e) Lead (II) hydroxide f) Hydrofluoric acid g) Iron (II) sulphide h) Tin (IV) oxide i) Nitric acid j) Rubidium iodide k) Sodium carbonate l) Barium hydroxide m) Cadmium oxide n) Nickel trichloride o) Mercury (II) hydride p) Silver phosphate q) Diarsenic pentaoxide r) Gold (III ) iodide s) Hydrogen peroxide t) Platinum tetrabromide 8.- Give the name of the following chemical substances: a) NH 3 b) CoO c) SrH 2 d) Cs 2 SO 4 e) Pt(OH) 2 f) PF 3 g) Ca(NO 2 ) 2 h) AgI i) PdO 2 j) B(OH) 3 k) BaBr 2 l) HClO 4 m) Au 2 O n) CdCl 2 o) RbH p) SeO 3 q) SbCl 5 r) SnO s) HI t) BeO Write the formula or give the name of the following chemical substances: a) Calcium sulphate b) Boron trifluoride c) Lead (II) hydroxide d) Hydrosulphuric acid e) Iron (III) oxide f) Nitric acid g) Palladium monoxide h) Mercury (II) hydride i) Diantimony trioxide j) Sodium peroxide k) NH 3 l) SeO 3 m) SrH 2 n) Pt(OH) 2 o) PF 3 p) AgNO 3 q) HClO 4 r) CdCl 2 s) CoS t) BeO 2

7 Unit 5: Inorganic Nomenclature 10.- Write the formula or give the name of the following chemical substances: a) FeO b) CuH c) AgCl d) HNO 2 e) CaSO 3 f) Lead (IV) oxide g) Phosphorus trifluoride h) Aluminium bromide i) Carbonic acid j) Potassium perchlorate 11.- Fill the table : FORMULA Covalent substances Common name / Stock 1 CF 4-2 CoO 3 SrH 2-4 NH 3-5 Pt(OH) 2 6 AgI - 7 SO 2-8 H 2 Se 9 Au 2 O - 10 SbCl 5-11 Potassium oxide 12 Sodium hydride 13 Boron trifluoride 14 Lead (II) hydroxide 15 Hydrofluoric acid 16 Iron (III) sulphide 17 Tin (IV) oxide 18 Mercury dibromide 19 Rubidium iodide 20 Sulphur hexafluoride 12.- Write the formula or give the name of the following substances:

8 Unit 6: Chemical reactions & stoichiometry 1.- Calculate the number of moles and molecules which are found in 5 grams of graphite (carbon), 125 grams of water and 250 grams o gypsum (calcium sulphate). Atomic masses: carbon: 12; hydrogen:1; oxygen: 16; sulphur: 32; calcium: 40 Sol: 0.417, 6.94 and 1.84 moles; , and molecules 2.- Calculate the number of moles and molecules in the volume of air inside a classroom, which has 30 m 2 and its height is 4 m, at 25º C and 745 mm Hg. Calculate the mass of air, knowing that the average molecular mass of air is 28,8 g.mol -1 Sol: 4810 moles; molecules; 137 kg 3.- A tennis ball contains about 40 g of sulphur hexafluoride. How many moles of this substance are inside the ball? What is the pressure of the gas, knowing that the volume of the ball is 300 cm 3 at 20º C? Sol: 0.27 moles; 21 at 4.- A gas cylinder contains 5 kg of butane, whose formula is C 4 H 10. Calculate the number of moles of butane and the number of molecules which are inside the gas cylinder. What is the pressure inside the cylinder if its volume is 2 l? What is the volume of this amount of gas at 700 mm Hg and 20º C? Sol: 86.2 moles; molecules; 1035 at; 2250 litres 5.- A 2.5 litre-gas cylinder filled with oxygen (O 2 ) contains 500 g of gas. Calculate the pressure inside the cylinder at 25º C. What is the pressure inside the cylinder? What is the volume occupied by this amount of gas at 30º C and 700 mm Hg?. 1 at = 760 mm Hg Atomic mass of oxygen: 16 Sol: 170 at; 421 litres 6.- Four grams of sulphur react with grams of fluorine, producing a compound made up of these two elements. Calculate the mass of product and the formula of this substance Atomic masses: sulphur: 32; fluorine: 19 Sol: g; SF The combustion of 3 tones of coal, which has 3 % of sulphur, produces sulphur dioxide and, eventually, acid rain. Balance the chemical equation and calculate the mass od sulphur dioxide produced and its volume at STP (Standard Temperature and Pressure). Atomic masses: sulphur: 32; oxygen: 16 Sol: 180 kg; 63 m Natural gas is mainly methane, whose formula is CH 4. Write the chemical equation of the combustion of this substance, in which methane and oxygen yields carbon dioxide and water. What is the mass of carbon dioxide produced by the combustion of 1 m 3 of natural gas at 25º C and 1.5 at? How many litres of oxygen at 20º C and 740 mm Hg do we have to use to carry out the combustion? 9.- The reaction between magnesium hibride with water yields magnesium hidrde and hydrogen (H 2 ). Write and balance the chemical equation. Id a 20 grams-pill of magnesium hibride reacts with water, how many moles and molecules of water do we need? What is the mass of magnesium hydroxide produced? What is the volume of hydrogen, at 15º C and 730 mm de Hg formed? Sol: 0,77 moles; 9, molecules; 44,6 g; 38 l 10.- The reaction between calcium carbide, CaC 2, and water yields calcium hidroxide and acetylene (C 2 H 2 ). Write and balance the chemical equiation and calculate the mass of water needed to produce 200 g of acetylene Sol: 277,2 g 11.- Calculate the volumen of oxygen at STP needed to burn 10,4 litres of acetylene at the same conditions. What is the volume of air (whose composition is 20 % oxygen and 80 % nitrogen) at 17º C and 700 mm de Hg Sol: 26 l; 150 l