LESSON 6: NUMBERS AND MEASUREMENTS ( adapted from A. Rozkošná materials) I. Discuss the questions below in your groups/pairs. 1. Do you have any lucky/unlucky number? Do you believe in numerology? 2. “Mathematics is the father of all sciences.”, “Everything in science has its origin in mathematics.”, Mathematics is the most primary science.” – do you agree with these statements? Why? Why not? 3. What could you calculate or measure ( express in numbers) in this room? 4. What are the things that these people need to calculate? a. biologist b. astronomer c. physicist d. geologist e. chemist II. Read these numbers or fractions: 0.2 3000 000 000 0.05 7000 000 000 000 26 1st 138 2nd 2479 (ordinal number/hotel room) 43^rd 503349777 (telephone number) 2000 000 2,053 67^th 2.053 (g/kg) 1/3 3/5 III. Simple arithmetics Look at the way we say these examples: 4 + 4 = 8 four and (plus) four is / equals eight 9 − 2 = 7 nine minus two is seven 5 × 5 = 25 five times five is twenty-fine or five multiplied by five is twenty-five 8 ÷ 4 = 2 eight divided by four is two Here are some more arithmetical symbols. Notice how to say them. 2^2 two squared square root of … - 2^3 minus (negative) two cubed cube root of … 2^4 two to the power of four π pi log[10]7 log of seven to the base ten x=3(a+b) x equals three, bracket a plus b, bracket IV. Work in pairs. Solve these maths problems. a) 12 − 6 = … d) = … g) = … b) 9 × 5 = … e) h) 2^4 = … c) 30 ÷ 6 = … f) 9^2 = … i) π = … Look at this example: Add six to seven. Now multiply by four. Subtract four. Divide by twelve. What is the answer? 6 + 7 = 13, 13 × 4 = 52 52 − 4 = 48 48 ÷ 12 = ? Work in pairs. Write down graphical image of the problems below, then take turns in saying them aloud and finding the answer (one of you should say the equation and the other should give the answers without looking at the paper). See how quickly you can do it. a) Multiply 7 by 9. Add 9. Divide by 6. Subtract 3. What is the answer? b) Subtract 8 from 24. Divide by 2. Add two. Multiply by 10. What is the answer? c) Add six to eight. Multiply by 10. What is the answer? d) Take 50% of the students in your class. Multiply by 2. Divide by 4. What is the answer? V. Units of measuremet. 1. Give the names of measurement units missing in the table below: QUANTITY UNIT ABBR. NOTES SI BASE UNITS length mass time temperature K =39.36 inches/in =2.2 pounds/lb SI DERIVED UNITS area volume velocity density frequency accelaration force work/energy/heat amount of substance molar concentration mol/m^3 NON-SI UNITS USED IN CHEMISTRY volume typical radius of an atom about the mass of a proton or neutron · ____________ · ____________ =1000 cm^3 =10^-10 m =1.66054x10^-27kg 1/12 of the rest mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state Some more measurements and their units: electric current ampere (amp) electric power watt (W) electric resistance ohm (Ω) electric potential difference volt (V) temperature degrees Centigrade (°C)/ Farenheit (F) 2.Work with a neighbour. Complete the table and then describe these numbers: Example: a) One kilometer equals a thousand meters or ten to the power of three a) kilo- one thousand: 1 km = 1000 m 10^3 b) deci- one tenth: 1 dm = m 10^ c) centi- one hundredth: 1 cm = m 10 d) milli- one thousandth: 1 mm = m 10 e) micro- one millionth: 1 μm = m 10 f) nano- one thousand millionth: 1 nm = m 10 g) pico- one picometer: 1pm 10 h) one_____________ : 1fm 10^-15 i)atto- one _____________ : 1__m 10^-18 VI. Percentages 65% (per cent) of our body weight is oxygen. Our body contains 65% of oxygen. Oxygen represents 65% of our body weight. Describe the rest of the diagram below using the structures given VII. Reading simple equations^1: here are some common compounds, their names and FORMULAS: NaCl – sodium chloride H[2]SO[4] – sulphuric acid ZnSO[4] – zinc sulphate C[6]H[6 ] - benzene ZnO – zinc oxide HCl – hydrochloric acid Na[2]CO[3] – sodium carbonate NH[3] - ammonia CO[2 ] - carbon dioxide NaOH – sodium hydroxide These formulas are useful for writing EQUATIONS. [] Example: HCl + NaOH → NaCl + H[2]O We spell as: H Cl plus Na OH gives Na Cl plus H[2]O We read as: hydrochloric acid reacts with sodium hydroxide to form sodium chloride and water. combines with Complete these equations. a) CuO + H[2 ]→ ……………………………… (copper oxide reacts with hydrogen to form copper and water) b) Na[2]CO[3] + 2 HCl → ………………………….. (sodium carbonate reacts with hydrochloric acid to form sodium chloride, carbon dioxide and water) c) Zn + 2HCl → …………………………… (zinc reacts with hydrochloric acid to form zinc chloride and hydrogen) Express these equations in words: 1. 2 Na + Cl[2 ]→ 2 NaCl ................................................................................................... .................... 2. ZnO + H[2]SO[4 ]→ 2 ZnSO[4] + H[2]O ................................................................................................... 3. 2 Na + 2 H[2]O → 2 NaOH + H[2 ................................................................................................... ........................................................] VIII. Watch the beginning of the video lecture about pH calculation given by Dr.Goldwhite.^2 Do the calculation, then watch the remaining part of the video and see whether you were right Useful vocabulary: acid (n ) - kyselina base (n) – zásada obtain (v) – získat strongly acidic (adv+adj) – silně kyselé basic (adj) - zásadité species (n) - vzorek concentration of a solution (n) – koncentrace roztoku ion (n) - iont X. Say whether the following statements are true or false. Correct the false statements. a) Duration is measured in degrees Centigrade T/F b) The second is a unit of time T/F c) Speed is measured in kilograms per hour. T/F d) The watt is a unit of electrical charge. T/F e) Density is measured in grams per metre cubed. T/F f) The gram is a unit of mass. T/F g) Liquid measurements are made in litres, or cubic decimetres. T/F GRAMMAR REVISION: COUNTABLE/ UNCOUNTABLE NOUNS I. Divide the words below into two categories: countable and uncountable nouns percentage, metre, science, molecule, nitrogen, information, radius, second, temperature, heat, fraction, chemistry, base, acid, petroleum, research, change, salt, object, ion, water, light, substance, matter, energy, electron, equilibrium, neutron II. Complete the sentences below with “many”or “much” 1. How ___________ electrons does an atom of carbon posses? 2. How ___________ elements are there in the periodic table? 3. How ___________ liquid does a beaker contain? 4. How ___________ chemical elements does the atmosphere contain? 5. How ___________ nitrogen does the atmosphere contain? 6. Do you find __________ useful information about chemistry on the Internet? 7. Will we exploit ____________ more nuclear energy in the future than we do today? What do you think? III. Complete the sentences with “little”, “a little”, “few”, “a few” 1. As very _____________ research has been done in the field, we still have no antidote to the disease. 2. Doing just _____________ research threw up some very useful information. 3. Only _____________ scientists were invited to take part in the project. That is probably why it was not successful. 4. The project team consists of _____________ well-known chemists. ^ Week 6 – Numbers and Measurements - Vocabulary four and (plus) four is / equals eight čtyři plus čtyři se rovná osm nine minus two is seven devět mínus dva je sedm beaker kádinka five times five is twenty-fine / five multiplied by five is twenty-five pět krát pět je dvacet pět eight divided by four is two osm děleno čtyřmi je dva two squared dva na druhou minus (negative) two cubed mínus dva na třetí two to the power of four dva na čtvrtou square root of … druhá odmocnina cube root of … třetí odmocnina three quarters tři čtvrtiny a third třetina one thousandth/one over a thousand jedna tisícina / jedna lomeno tisíc How much is five and four? Kolik je pět plus čtyři? one thousand two hundred and fifty-eight tisíc dvěsta padesát osm add (v) přičíst subtract (v) odečíst One kilometre equals nought point six two one miles. Jeden kilometr se rovná nula celá šedesát dva mil. 7. 65 per cent of our body weight is oxygen. 7,65 procent těledné váhy je kyslík. Hydrochloric acid reacts with sodium hydroxide to form sodium chloride and water. Kyselina chlorovodíková reaguje s hydroxidem sodným a vytvoří chlorid sodný a vodu. sodium chloride chlorid sodný carbon dioxide oxid uhličitý sulphuric acid kyselina sírová sodium hydroxide hydroxid sodný sodium carbonate uhličitan sodný acid (n ) / acidic (adj) kyselina / kyselý base (n) / basic (adj) zásada / zásaditý obtain a species (v) získat vzorek ion (n) iont concentration of a solution (n+prep+n) koncentrace roztoku surface area (n+n) povrch width (n) šířka length (n) délka square metre (adj+n) metr čtvereční cubic metre (metre cubed) (adj+n) metr krychlový electric current (adj+n) elektrický proud electric power(adj+n) elektrický výkon electric resistance (adj+n) elektrický odpor temperature (n) teplota degree Centigrade (n+n) stupeň Celsia kilometres per hour kilometry za hodinu Second is a unit of time. Sekunda je jednotka času. Sources: Lesson based on Bates, Martin and Dudley-Evans, Tony: Nucleus of General Science. Longman 1990. Adapted from Cihová, Jarmila et al. Angličtina pre študentov chémie. Bratislava: Univerzita Komenského, 2003. ^ Available at ^http://www.youtube.com/watch?v=LZk1_yzF9js. Accessed 29th October 2010.