1|2 HAVO|VWO TTOPHYSICS AND CHEMISTRY
ANSWERS PART A
AUTHORSR. CREMERSP. VAN HOEFLAKENF. KANM. KELDERL. LENDERSP. OOSTERLAAKC. SCHATORJÉT. SEYNAEVER. TROMP
EDITINGS. MICHON
TRANSLATIONMIKE WILKINSON/TESSERA TRANSLATIONS BV
2021 releasemalmberg/nova-natuurkundeMalmberg, ’s-Hertogenbosch
Contents
1 Natural sciences 5
THEORY
1 A new subject 62 Research 83 Experiments 10
2 Substances 12
THEORY
1 Substances in the home 132 Pure substances and mixtures 173 Mass and volume 204 Density 25EVERYDAY SCIENCEGold: genuine or fake? 31
3 Water 32
THEORY
1 Ice, water, water vapour 332 Temperature 363 Phase changes 404 Boiling point and melting point 43EVERYDAY SCIENCEThe explosive power of steam 47
4 Electricity 48
THEORY
1 Making an electrical circuit 492 Voltage sources 523 Circuits 554 Power and energy 59EVERYDAY SCIENCEA solar energy competition 63
Ch 1 Natural sciences Answers 1 - 2 havo/vwo TTO
1 Natural sciences
Ch 1 Natural sciences Answers 1 - 2 havo/vwo TTO
6
A new copper roof has been put on a building (figure 8a). A few years later, the effects of the rainand air have turned the copper green (figure 8b). This is called oxidation.Oxidation would be studied in physics / chemistry because the copper on the roof has / has notchanged into another substance.
7
Have a look at figure 9.a What changes when you pull on a spring? The spring gets longer.b Explain that this can be a temporary change or a permanent one. If you don’t stretch the spring too far, the distortion is temporary: as soon as you stop pulling on the spring, it goes back to its original length. If you pull on the spring too hard, it will get damaged. It will then lo longer go back to its original length when you stop pulling on it.
[STER] 8
Sometimes several changes can happen at the same time.What changes when an iron nail is heated with a Bunsen burner? A change in length, a change in colour when the nail starts to glow and even a phase change if the nail is heated so strongly that it melts.
9Figure 10 shows you an X-ray of a man’s neck and part of his head.a Which absorbs more X-rays: the muscles or the bones?The bones absorb more X-rays.b What has this man got in his throat?a safety pinc What will that object be made of?It is made of a metal – probably steel.d Does that material absorb a lot of X-rays or not very much?Metals absorb X-rays well.
10 Rolina has broken her leg. An X-ray of the fracture is taken in hospital. Why do they use as little X-ray radiation as possible for this? Because X-rays are harmful to your body, the amount of radiation used is kept to a minimum.
11
X-rays are not only used in hospital.What does security at an airport use X-rays for? To see if there are forbidden or dangerous items inside a suitcase. The customs agents can see that without having to open the suitcase.
Ch 1 Natural sciences Answers 1 - 2 havo/vwo TTO
2 Research
COURSE MATERIAL
1
Why should you never taste a substance in physics or chemistry? Because the substances used in physics and chemistry can be toxic.
2
Which unit belongs with which variable? A length 1 kilogram A = 3 B mass 2 litre B = 1 C time 3 metre C = 4 D volume 4 second D = 2
3
Insert the correct words into the text.An indicator lets you find out whether a specific substance is present or not.The indicator changes colour under the influence of that substance.If you add iodine to starch, the colour of the iodine changes from yellow-brown to dark blue.
IN PRACTICE
4
You use your senses to make observations.Which sense are you using? A hearing 1 skin A = 4 B taste 2 nose B = 5 C smell 3 eyes C = 2 D touch 4 ears D = 1 E seeing 5 tongue E = 3
5Does each of these sentences belong with the study question or the conclusion of a piece ofresearch?a Can electricity pass through a plastic tube? study question / conclusionb Who is the tallest person in this class? study question / conclusionc The sun rises in the east every day. study question / conclusiond Serge wants to know how high the classroom ceiling is. study question/ conclusione Paper burns more easily than wood. study question / conclusionf Nick is the tallest person in the class. study question / conclusion
6[VA] See the skills section on Doing research.Read figure 4 closely.Think up a research question yourself that would suit this text.For example:
- What is the e-bike’s maximum speed?
- Can Evelyn get to school and back on a fully charged battery?
- How long does the trip from home to school take?
Ch 1 Natural sciences Answers 1 - 2 havo/vwo TTO
3 Experiments
COURSE MATERIAL
1
Figure 9 shows four items of equipment for experiments that are all made of glass.Write down the name of each piece of glassware.1 round-bottomed flask2 conical flask3 glass beaker4 measuring cylinder
2
There are various safety rules for experiments.Write down three safety rules. For example: Don’t run. Wear safety goggles. Work neatly. Tie long hair back. Other answers may be correct too.
3When you are lighting a Bunsen burner, the air control ring must be open / closed.
4
Have a look at figure 10.Which clock is analogue and which is digital? Explain how you can see that. The clock on the left is an analogue clock. It has pointers and a graduated scale. The clock on the right is a digital clock. It has a screen with numbers on.
IN PRACTICE
5
Read the sentences about things you could do in an experiment.Write down whether what is happening is correct or incorrect.a Kylie puts her nose up against a bottle to sniff what’s in it. correct / incorrectb Ranjev is holding the test tube in a flame using the test tube tongs. correct / incorrectc Carl takes his safety goggles off while he is heating a liquid. correct / incorrectd Karen has long hair that she has tied into a ponytail hanging down her back. correct / incorrecte Elaine slides her bag under the bench before she starts on the experiment. correct / incorrectf Paul tastes a substance to see if it is sweet. correct / incorrectg Sarah leaves the practical lab for a talk with her mentor, so she turns the Bunsen burner down to a yellow flame. correct / incorrect
6Chloe accidentally knocks over her Bunsen burner. The Bunsen’s flame stays alight. Chloe panicsbut you stay calm because you know the right thing to do first.( ) A You turn off the gas tap on her bench.( ) B You pour a glass of water over the Bunsen.( ) C You take the fire extinguisher and use it to put the Bunsen burner out.( ) D You take hold of the Bunsen and put it the right way up again.( ) E You try to comfort Chloe.
Ch 1 Natural sciences Answers 1 - 2 havo/vwo TTO
7
Write down five safety features in the practical lab in your school. Examples: emergency shower, eyewash bottle, fire blanket, fire extinguisher, sand bucket, safety goggles, emergency exit
8In an experiment, you will be heating two glass beakers of water, one containing 100 mL waterand the other containing 2 L. You have to measure the temperature every 30 s using athermometer. You make a graph of each series of measurements, plotting the temperatureagainst the time.a Which flame do you use in the following situations?
- First you heat the glass beaker with 100 mL water.silent blue flame
- You make a graph of the measurements for the small glass beaker.luminous (yellow) flame
- You heat the large glass beaker with 2 L water.roaring blue flame
- You make a graph for the large glass beaker with 2 L water.No flame at all: you’ve finished measuring so the Bunsen burner can be turned off.b Why do you have to be very careful when heating the small glass beaker of water inparticular?If there is a thermometer in it, the glass beaker could easily tip over.
[STER] 9 Natural gas needs oxygen to burn. When the Bunsen burner is being lit, the air control ring is closed so that no air can flow through the barrel along with the gas. Explain why it is still possible to light the Bunsen. There is also oxygen in the air around the top of the Bunsen. That oxygen means that the gas is still able to burn.
[STER] 10 John has two identical candles. a Explain how he can make a clock from one of them, using the other. He places the candles next to each other and lights one of them. At the same time, he starts a stopwatch. After a certain time (for example 10 min), he puts a mark on the unlit candle at the level that the burning candle is down to and he labels the mark “10”. He repeats that every ten minutes until the first candle has burned away. The other candle now has a graduated scale showing the time it has been burning. When that candle is lit, the time can be read off. b What are the disadvantages of this candle clock? Examples: You can only use this clock once. The maximum time interval you can measure with this clock is limited: until the candle has burned away completely. This clock is not very accurate.
Ch2 Substances Answers 1 - 2 havo/vwo TTO
1 Substances in the home
COURSE MATERIAL
1
In physics and chemistry, we often talk about the ‘properties of a substance’.a What is meant by a ‘property’ of a substance? A property of a substance is a characteristic that you can use to recognize a substance.b Give four examples of substance properties. colour; odour; taste; flammability
2List one or two distinctive properties of each of the following substance.a copper flammability / smell / colour / tasteb petrol flammability / smell / colour / tastec sugar flammability / smell / colour / tasted alcohol flammability / smell / colour / taste
3Three substances are on a desk in a laboratory:
- a corrosive substance;
- a flammable substance;
- an oxidizing substance.a Explain why each of these substances is hazardous.A corrosive substance can severely affect not only materials such as iron but also the eyesand skin. A flammable substance can be set alight very easily. An oxidizing substance canmake burning substances burn more easily or more intensely.b Write down which symbol from figure 3 belongs with which substance.
A corrosive substance 1 A = 6
B flammable substance 2 B = 4
C oxidizing substance 3 C = 3
D toxic substance 4 D = 2
E harmful or irritant substance 5 E = 1
F explosive substance 6 F = 5
Ch2 Substances Answers 1 - 2 havo/vwo TTO
IN PRACTICE
4
Write down a distinctive property of:a vinegar. the taste (sour)b lead. the colour (grey)c olive oil. the taste (and odour and colour)d methylated spirits. the odour and the flammability
5
Carl has a bottle of mineral water, a bottle of alcohol and a bottle of white spirits in his shed. Thelabels on the bottles are so old that they are illegible. The three bottles look identical too.a How can he find out which substance is in which bottle? Carl should open the bottles and waft a little bit of the odour towards his nose. Water is odourless, white spirits have a very characteristic smell and alcohol tingles.b What property of these substances can he therefore use to tell them apart? He can recognize the substances from their smells.
6
The same substance can occur in forms that look very different.a What can sugar look like? Think of how sugar is sold. Sugar can occur as lumps, as large or small crystals, and it can also be powdered.b What can water look like (for example in various weather conditions)? Water can occur as: - a solid substance (ice, hail, snow, sleet); - a liquid (rain, dew); - a cloud (mist).
[STER] 7 When you are working with hazardous substances, the rule is that ‘prevention is better than cure’. Car drivers who are smoking should therefore put their cigarettes out before filling up with petrol. Write down a suitable safety precaution (think one up yourself) for someone who is: a unblocking a blocked drain with drain cleaner (which is corrosive). They could then: - put gloves on; - wear protective clothing; - wear safety goggles. b cleaning a door before painting it, using a very dilute ammonia solution (irritating to the eyes, the skin and the mucous membranes of the mouth and lungs). They could then: - ventilate the room properly; - wear a breathing mask; - put gloves on; - wear protective clothing; - wear safety goggles. c getting grease stains out of their trousers with white spirit (which is flammable). They could then: - work in a well-ventilated room; - work outside; - put out any flames that are nearby first.
Ch2 Substances Answers 1 - 2 havo/vwo TTO
c on the packaging of a flammable substance. Possible P-phrases are: P210: Keep away from heat/sparks/open flames/hot surfaces. No smoking. P211: Do not spray on an open flame or other ignition source. P241: Use explosion-proof electrical/ventilation/lighting equipment. P242: Use only non-sparking tools. P243: Take precautionary measures against static discharge.d on the packaging of an oxidizing substance. Possible P-phrases are: P210: Keep away from heat/sparks/open flames/hot surfaces. No smoking. P220: Keep/store away from clothing/combustible materials. P221: Take any precaution to avoid mixing with combustibles. P270: Do not eat, drink or smoke when using this product. P370 + P378: In case of fire: use ... for extinguishing
Ch2 Substances Answers 1 - 2 havo/vwo TTO
2 Pure substances and mixtures
COURSE MATERIAL
1
What is a molecule? a very tiny particle that makes up a substance
2
What is the chemical term for a substance:a that is made up of different sorts of molecules? a mixtureb that is made up of only one kind of molecule? a pure substance
3Are the following statements true or false?a When you make coffee, you are using water as a solvent. true / falseb Solutions are always colourless (just like water). true / falsec A suspension does not remain perfectly mixed over the course of time. true / falsed A suspension is clear: you can see through it. true / falsee Suspensions and solutions are not pure substances. true / falsef Most substances in daily life are mixtures. true / false
4Insert the correct words into the text.a Ground coffee beans contain a lot of different aromas and flavourings.b These substances dissolve when you pour hot water over the ground coffee.c The substances that do not dissolve in water remain in the filter.d The freshly made coffee in the coffee pot is called the filtrate.e The coffee grounds left in the filter are called the residue.
IN PRACTICE
5
Say whether you think each of these liquids is a solution or a suspension and why.a Tea with sugar (and no milk) is a solution / suspension because it is cloudy / clear. The liquid stays / does not stay thoroughly mixed.b Orange juice is a solution / suspension. The liquid stays / does not stay thoroughly mixed because the bits of fruit pulp sink / do not sink to the bottom.c An energy drink is a solution / suspension because it is cloudy / clear.d Yoghurt is a solution / suspension because it is cloudy / clear.
6Charlotte puts a spatula-tip of white powder into a test tube. She adds distilled water and shakesit. Figure 6 shows you what the contents of the test tube look like, just after shaking it (left) andone hour later (right).a How can you tell that the white powder was not dissolved?The mixture is cloudy.b What kind of mixture was obtained by shaking?a solution / suspensionc What happened to the white powder after an hour?The white powder sank to the bottom of the test tube.
Ch2 Substances Answers 1 - 2 havo/vwo TTO
c A site with household tips says “You can remove greasy stains from fabrics by dabbing them with spirits such as vodka.” Explain why the stains disappear when dabbed with vodka, but not if pure water is used. Greases and fats dissolve in alcohol. Because vodka contains a lot of alcohol, the grease dissolves in vodka too. The grease does not dissolve in water.d Glands in your skin produce greases that protect the skin against drying out. Explain why your skin can feel dry if it comes into contact with ethanol a lot. The grease (fat) in the skin dissolves in ethanol. Your skin is then no longer protected against dehydration and it will feel dry.
11
A perfume is a mixture of various aromatic substances in a solvent. In most perfumes, that solventis alcohol.a As long ago as Roman times, people pressed flowers to get aromatic substances that could be used in ointments, oils and other products. In the Middle Ages, the Arabs discovered that alcohol improved the shelf life of these aromas considerably. Why was this discovery important? This discovery made it possible to produce perfumes that would keep for a long time.b Between 20% and 30% of a perfume consists of aroma substances, dissolved in alcohol. Aromatic substances make up 5% to 10% of an eau de toilette and 2% to 3% of an eau de cologne. Explain why a perfume is more expensive than an eau de cologne. Aromatic substances are expensive raw materials. They are more costly than solvents such as ethanol. The higher the percentage of aromatic ingredients in a perfume, the more expensive the product is to make.c Explain what happens to the ingredients of a perfume when you put perfume on. The alcohol evaporates fairly quickly, but the aromatic substances are left behind on the skin. These are the substances you can smell. After a while, the aromas will evaporate or sublimate too.d You are going to try out a new perfume in the shop and you want to know whether it smells nice. Why is it better not to smell the perfume straight after putting it on? This is because your nose may get temporarily numbed by the solvents as they evaporate.
Ch2 Substances Answers 1 - 2 havo/vwo TTO
3 Mass and volume
COURSE MATERIAL
1
Explain:a how you can measure the mass of a quantity of a solid substance. using scalesb how you can measure the volume of a quantity of a liquid. using a measuring cylinderc how you can determine the volume of a rectangular block. You can measure the length, width and height of the block with a ruler or drafting protractor, for example. You calculate the volume using this formula: V = l · w · h.d how you can determine the volume of a pebble. You use the immersion method for this. That comprises the following steps: 1 Fill a measuring cylinder with water to a given level. 2 Read the initial level. 3 Lower the object carefully into the water. 4 Read the final level of the water. 5 Calculate the volume by subtracting the initial level from the final level.
2
Convert.a 1 kg = 1000 gb 1 g = 1000 mgc 1 m 3 = 1000 dm 3d 1 dm 3 = 1000 cm 3e 1 L = 1000 mLf 1 mL = 1 cm 3
IN PRACTICE
3
Many packages state the mass of the contents in grams or kilograms.Calculate the missing data and use it to complete table 1.[VA] See the skills section on Working with prefixes.
table 1 The contents in grams and kilograms.The contents of a have a mass ofbag of sugar 1000 g = 1 kgpacket of couscous 500 g = 0 kgbag of noodles 400 g = 0 kgpack of butter 250 g = 0 kgpacket of cocoa powder 100 g = 0 kgshaker of pepper 50 g = 0 kg
4
Convert.[VA] See the skills section on Converting units.a 250 g = 0 kg f 1 kg = 1300 gb 0 kg = 625 g g 0 t = 250 kgc 0 g = 500 mg h 0 kg = 750 gd 350 mg = 0 g i 810 kg = 0 te 0 g = 35 mg j 8 mg = 0 g
