3 3
4 8
4 2 8 2
2 10 2,5 10
25 10 60 25 10 6 6 5 10
10 1 6 ) 10 5
( ⋅ − × ⋅ = ⋅ − × ⋅ = ⋅ = ⋅ = ⋅
Uitwerkingen hoofdstuk 1 versie 2014
1. Rekenen met grote en kleine getallen.
Opgave 1.1 Schrijf de volgende notatie zo kort mogelijk
a 6 6
2 10
3 2
2 5
2
10 10 2
10 2 10 )
10 (
10 2 ) 10
( × ⋅ = ⋅
⋅ =
×
b 6 6 4
2 6
2 3
2 3
2
10 10 2
10 2 )
10 (
10 2 )
( −
⋅
⋅
⋅
⋅ =
= ×
⋅
× a b a a b
b
c 6 6 6
3 3
3 2
3 3
2 10 1 10
2 1 )
10 ( 2
)
( −
⋅
⋅
−
⋅ =
×
⋅
= −
×
−a a a a a
d a2+3a2 =1⋅a2+3⋅a2 =4a2
e a2 +a3 =1⋅a2 +a⋅a2 =(1+a)⋅a2 of a2(a+1) is niet echt korter, dus laten staan is ook goed!
f (−3a2)3 =(−3)3⋅(a2)3 =−27a6
g 3 6 3
6
3 3 2 3
2 ( )
)
( = = of a ⋅b−
b a b a b
a
Opgave 1.2 Schrijf als macht of getal in SCI-mode.
a 23 27 27
4
3 10 10 1
6 2 10 6
10
2 − − −
⋅
=
⋅
⋅ =
⋅
b 8 15 5
3 15
4 2
3 3 5
) (
)
( x y
y y x y
y
x ⋅ = ⋅
⋅ =
−
−
−
−
c 1
1
1−319 = 3191 = d 230 = 1
e (a+b)0 =1
f 52×5⋅102 =53⋅102
g 1−319 = 1 zelfde opgave als c) h (−1)399 =−1⋅(−1)398 =−1 i (−1)400 =1
j 2 2 2 4 2 4 10 6 4 10 6
25 10 100 5 10 1 5 ) 10 5
( ⋅ − = − ⋅ − = ⋅ − = ⋅ − = ⋅ − = k (0,1)4 =(10−1)4 =10−4
l
Opgave 1.3 Vul de ontbrekende exponent in.
a 33×34 =37
b 123×23 =(22×3)3×23 =26⋅×33×23 =29×33
c 3 6 2 3 3 9 5
2 3
3 2
3 2 3 2 3 ) 2
3 2 (
) 3 2 ( 6
24 = × × × = ⋅
×
= × −
−
d 3 2 6 6 6
0
3 ) 2
3 2 (
1 )
6 (
16 = ×
= × −
−
e 2 2 2 0
2
2 2
3 2 2
1 ) 8 2 (
8 16
8 = = ⋅
= × −
f 4 2 4
2
4 2
5 ) 3
5 3 (
3 15
3 − −
×
× =
=
g 4 2 2
2
4 2
5 5 2
) 5 2 ( 5
10 −
×
× =
=
h 2 0
2
10 10 =a
h 0 = ⋅ −1⋅0 −1
⋅ J kg C
C kg
J
Opgave 1.4 Oefenen met vermenigvuldiging van machten.
Maak eerst een schatting en controleer vervolgens met je rekenmachine.
a (102)3,1 ≈106 met rekenmachine (102)3,1 =1,58⋅106!
b 11 17
6 3
11 3 2
10 10 2
4 10 2 10
4 ) 10 1 , 2
( ≈ ⋅
⋅
≈ ⋅
⋅
⋅
−
−
c 3 21
18 3 3 6
10 10 10 1 999
) 10 1 , 1
( − − −
⋅ ≈
⋅ ≈ d 1+10−5 ≈1
e 8 8
6 3 2 3
10 8 12 10
100 12 10 12
) 10 ( 12
) 011 , 0
( − − − −
⋅
≈
⋅
≈
≈
≈
f 8 14
3 3
3
8 3 3
10 10 4
4
10 2 10 2 10
2 , 4
10 2 ) 10 2
( ≈ ⋅
×
×
×
≈ ×
⋅
⋅
×
⋅
−
−
g 6 6 6 10 7 2,5 10 7
4 10 10 4 1 10 4
1 10
4 02 ,
1 − − −
⋅
≈
⋅
≈
⋅
⋅ ≈
⋅ ≈
h 0,25
4 1 10 4
) 110 , 2 (
0 0 2
≈
⋅ ≈
i 1,5 10 15
10 2
10 3 10 21 , 2
10 0 ,
3 1
3 4
3 4
=
⋅
⋅ =
≈ ⋅
⋅
⋅
j 1 3
4
1 4
10 10 2
2 10 4 10 21 , 2
10 16 ,
4 = ⋅
⋅
≈ ⋅
⋅
⋅
k 1 2
3 3
3
10 10 8
120 10 1000 1200
10 1000 1200
10 04 , 5
200 ≈ ⋅
⋅
= ⋅
≈ ⋅
⋅
×
l 2 10 20 210
2×2230 ≈ × ≈
m 2,5
12 30 10 12
10 3 300 400
300000
4 5
≈
⋅ ≈
≈ ⋅
×
Opgave 1.5 Welk getal is groter.
Maak eerst een schatting en controleer vervolgens met je rekenmachine.
a 3 3 5 10 3 5 10 3 6 10 3
200 1 6
6− = 1 ≈ ≈ ⋅ − ⋅ − < ⋅ − b (2⋅10−2)2 =4⋅10−4 4⋅10−4 <0,004
c 225⋅103 =2,25⋅105 2,25⋅105 >2,25⋅104
d 2 2 2 2 2 2
2 1 4
1 2
) 1 2 4 (
) 1 4
( − = of − = <
e 0,25 4 0,25
2 ) 1 2 ( 25 4
, 0
1 ) 5 , 0 ( ) 1 5 , 0
( −2 = 2 = = of −2 = 2 = >
Opgave 1.6 Gebruik van voorvoegsels.
In de natuurkunde en techniek werkt men met grootheden, eenheden en voorvoegsels.
Zet de volgende eenheden om en geeft het antwoord in SCI-mode.
a 4,78 Mg =4,78⋅106 g=4,78⋅109 mg b 4,12⋅10-3 m = 4,12⋅10−3×103 mm=4,12mm
c 200 L = h200×0,01hL=2,00hL d 0,0032 mL =0,0032×106 nL=3,2⋅103 nL
e 23,2·10-6 kg =23,2⋅10−6×109μg =2,32⋅104 μg
f 525000 N=5,25⋅105×10−3 kN=5,25⋅102 kN g 2⋅103 g =2⋅103×10−3 kg=2kg
Opgave 1.7 Schrijf zonder voorvoegsel en bij voorkeur in SCI-mode.
a 2⋅103 kg = 2⋅103 × 103 g = 2⋅106 g
b 2⋅10-3 mm = 2⋅10−3×10−3 m=2⋅10−6 m c 23,5 mL = 23,5×10−3 L=2,35⋅10−2 L d 1,89⋅102 μL =1,89⋅102×10−6 L=1,89⋅10−4 L e 2300 km =2300×103 m=2,3⋅106 m f 23,5 ms = 23,5×10−3s=2,35⋅10−2 s g 2,1 MA =2 ⋅,1 106A
h 700 nm =700×10−9 m=7×10−7 m i 23,5 GJ = 23,5×109 J=2,35⋅1010 JJ j 2,1 ns =2,1⋅10−9 s
k 340 mm2 =340×10−6 m2 =3,4⋅10−4 m2
moleculen 10
34 , 3
mol deeltjes 10
022 , 6 mol 10 55 , 5 N
mol 10 5,55 015 mol
, 18 g 1 1
g 1 cm cm 1
1g ) water mL 1 (
22
23 2
A
2 -
3 3
⋅
=
→
⋅
×
⋅
=
→
⋅
=
⋅
=
=
=
×
=
→
⋅
=
−
N
n mol
aantal N
m V m ρ
moleculen 10
08 , 3
mol deeltjes 10
022 , 6 mol 10 107 , 5 N
mol 10 5,107 015 mol
, 18
920 , g 0 920 , 0
g 920 , 0 cm cm 1
920 g , 0 ) ijs mL 1 (
22
23 2
A
2 -
3 3
⋅
=
→
⋅
×
⋅
=
→
⋅
=
⋅
=
=
=
×
=
→
⋅
=
−
N
N mol
aantal N
m V m ρ
H atomen 10
6,9 (H) : afgerond
atomen 10
47 , 3 2 ) H ( moleculen 10
47 , 3 ) O H (
mol deeltjes 10
022 , 6 mol 10 77 , 5 N
mol 10 77 , 5 015 mol
, 18
10 4 , mg 10 4 , 10
g 18,105 mol
1
mg 4 , 10 ) lucht L 1 in waterdamp (
20
20 20
2
23 4
A
4 3
⋅
=
⋅
×
=
→
⋅
=
→
⋅
×
⋅
=
→
⋅
=
⋅
× =
=
=
=
−
−
−
N
N N
N mol
aantal N
m
l 6,3·10-4 dm2 = 6,3⋅10−4×10−2 m2 =6,3⋅10−6 m2 m 2,1 mm3 =2,1⋅10−9 m3
Opgave 1.9 Eenheden converteren(omzetten) .
a 3,12·10-3 m/min = 3,12⋅10−3×103/60=5,20⋅10−2mm/s b 60 µm3 = 60×(10−6)3 =60×10−18 =6⋅10−17 m3
c 2,45 nm =2,45⋅10−9 m d 2,78·10-6 L/min =
cm s 10 63 , 4 60 / 10 10 78 ,
2 ⋅ −6× 3 = ⋅ −5 3
e 0,003 L = 0,003×(108)3 =3⋅1021 nm3 f 3·103 mm3 = 3⋅103 μL
g 60 ms =60×10−3 s=6⋅10−2 s i 340 GJ = 340×109 =3,4⋅1011 J
k 0,998·103 kg·m-3 = 0,998⋅103×103×10−6 =0,998g∙cm-3 Opgave 1.10 Rekenen met mol 1 .
a
b
c
g 10 99 , 10 2 022 , 6
015 , ) 18 O H molecuul 1
(
g/mol 015 , 18 ) O H (
23 2 23
2
⋅ −
⋅ =
=
= m g
M
g 10 674 , 10 1 022 , 6
g 008 , ) 1 proton 1 (
g 008 , 1 ) protonen 10
022 , 6 (
24 23
23
⋅ −
⋅ =
=
=
⋅ m
m
g 10 369 , 2000 8
) 1
) ( elektron 1
( = m proton = ⋅ −28
m
g 1,008 10
674 , 1 10 022 , 6 ) H mol 1 (
g 10 1,674 g
10 8,369 g
10 674 , 1 ) atoom H
1 (
24 23
-24 -28
24
=
⋅
×
⋅
=
⋅
=
⋅ +
⋅
=
−
−
−
m m
μL 10 24 , 5 10 10 10 24 , 5
m 10 24 , 5 m ) 10 0 , 10 6 (
6 1 1
7 6
3 16
3 16 3
3 6 3
−
−
−
−
⋅
=
×
×
⋅
=
→
⋅
=
⋅
⋅
⋅
=
→
⋅
⋅
= V
V d
V π π
μg 10 1,31 μg 10 10 31 , 1
kg 10 31 , 1 m 10 24 , m 5 2500kg
3 - 9
12
12 3
16 3
⋅
=
×
⋅
=
→
⋅
=
⋅
×
=
→
⋅
=
−
−
−
m
m V m ρ
Pa p
A p p Fz
3 2
4 2 2
10 2 , m 2 10 N 22 , 0
cm 22N , cm 0 400
N 88
⋅
=
×
=
→
=
=
→
= d
Opgave 1.11 Rekenen met mol 2 . a
b
c
Opgave 1.12 Rekenen aan bolletjes a
b
Opgave 1.13 Parachutist.
a Een versnelling van 9,8 m/s2 betekent dat de snelheid(v) toeneemt met 9,8 m/s per seconde of 0,98 m/s per 0,1 seconde.
v (na 1 seconde) ofwel v(1) = 9,8 m/s v (na 2 seconden) ofwel v(2) =
ms 6 , 19 8 , 9
2× = b Fz =m⋅g →Fz =80kg×9,81Nkg=785N
c Fw =Fz =785N want snelheidblijft hetzelfde d Fz =785N dezehangt alleen vandemassaaf e Fw =Fz =785N want snelheidblijft hetzelfde
f FN = Fz =785N FN is de kracht van de grond op de parachutist Opgave 1.14 Rekenen aan kracht en druk
a G=Fz →G =9,0×9,81=88,3N afgerondG =88N b
Pa p
A p p F
F G
z z
3 2
4 2 2
10 8 , m 1 10 N 18 , 0
cm 176N , cm 0 500
N 88 N 88
⋅
=
×
=
→
=
=
→
=
=
=
mbar 1013 mbar 1000 1,013 bar
013 , 1
cm 13N , 10 10 / 10 013 , m 1 10 N 013 , 1
hPa 10 013 , 1 Pa 10 013 , 1
bar 013 , m 1 10 N 013 , 1
2 4
5 2
5
3 5
2 5
=
×
=
=
=
⋅
=
⋅
=
⋅
=
⋅
=
=
⋅
=
b b b b
p p p p
N 10 afgerond
N 13 , 10 m 10 m 1
101300N 2× × 4 2 =
=
→
⋅
= p A F −
F
m 764 , 0 Nkg 81 , m 9 10 kg 5 , 13
m 101300 N
3 3
2
=
×
⋅
=
⋅ →
=
→
⋅
⋅
= h
g h p h g
p ρ ρ
2 2
4
2 3
cm 147N , cm 0 10 N / 1472
m 1472N m 15 , kg 0 81N , m 9 1000kg
=
=
→
=
×
×
=
→
⋅
⋅
= p
p h g p ρ
2 2
4
2 3
cm 0981N , cm 0 10 N / 981
m 981N m 10 , kg 0 81N , m 9 1000kg
=
=
→
=
×
×
=
→
⋅
⋅
= p
p h g p ρ
Pa 10 96 , 1 :
m 1962N m
200 , kg 0 81N , m 9 1000kg
3
2 3
1 1
⋅
=
=
×
×
=
→
⋅
⋅
=
→
=
gas gas
gas h
gas
p afgerond
p
h g p
p
p ρ
c
d 20cm
cm 500
cm 10
2 3 4
=
=
→
=
→
⋅
= h
A h V h A V
Opgave 1.15 Rekenen aan luchtdruk.
a 600 10 m 6078N
m 10 N 013 ,
1 ⋅ 5 2× × 4 2 =
=
→
⋅
= p A F −
F b
b
Opgave 1.16 Kracht = druk × oppervlak a
b
Opgave 1.17 Rekenen aan vloeistofdruk in vat.
a
b
Opgave 1.18 Bepalen van de gasdruk a
Pa 10 80 , 9 :
Pa 98038 Pa
1962 Pa 10
10
4 5
2 5
2
⋅
=
=
−
=
→
⋅
⋅
−
=
→
−
=
gas gas
gas h
atm gas
p afgerond
p
h g Pa p
p p
p ρ
Pa 10 02 , 1 :
Pa 101962 Pa
1962 Pa 10
10
5 5
3 5
3
⋅
=
= +
=
→
⋅
⋅ +
=
→ +
=
gas gas
gas h
atm gas
p afgerond
p
h g Pa p
p p
p ρ
m3
640kg 1 , 0 1 64
, 0 0800 , 0 800
1 , 0 81 , 9 0800
, 0 81 , 9 800
=
=
→
×
=
×
→
×
×
=
×
×
→
⋅
⋅
=
⋅
⋅
→
=
benzine benzine
benzine
benzine benzine
olie olie
benzine
olie p g h g h
p
ρ ρ
ρ
ρ ρ
mol 10 04 , 2 mol JK 8,314
JK 17 , 0
JK 17 , K 0
) 273 20 (
m 10 m 500
10 N
2 3 6 2
5
−
−
⋅
=
⋅
=
→
=
+ =
⋅
×
=
⋅ →
=
R n n C
T C V C p
moleculen 10
2 , 1 :
moleculen 10
228 , 1 10 022 , 6 10 04 , 2 10 022 , 6
22
22 23
2 23
⋅
=
⋅
=
⋅
×
⋅
=
⋅
⋅
= −
N afgerond
n N
g 90 , 0 ) ( :
g 8976 , mol 0 44g mol 10 04 , 2
2
2
=
=
×
⋅
=
→
⋅
= −
CO m afgerond
m M n m
lucht m
gas mL ppm 10
10 = 3
=
− waarde MAC
lucht m per mol 10 2 , 4 :
S H mol 10 158 , 4 mol JK 8,314
JK 10 457 , 3
JK 10 457 , K 3
) 273 20 (
m 10 m 10
101300 N
3 4
2 4
3
3 3
6 2
−
−
−
−
−
⋅
=
⋅
=
⋅
⋅
=
→
=
⋅ + =
⋅
×
=
⋅ →
=
n afgerond
R n n C
T C V C p b
Opgave 1.19 Bepalen van de dichtheid van een vloeistof met u-buis.
Opgave 1.20 Hoeveelheid gas meten.
a De massa van het gas wordt bepaald via de gasconstante.
b
c
Opgave 1.21 Maximaal aanvaardbare concentratie.
a
b
J 10 537 , 4 ) atoom per (
s m 10 kg
537 , 4 s) 10 m 9979 , 2 ( kg 10 048 , 5
kg 10 048 , 5 kg 10 6605 , 1 0304 , 0
u 0,0304 u
4,0026 - u 0330 , 4
12
2 12 2
2 8 29
29 27
2
⋅
=
→
⋅ ⋅
=
⋅
×
⋅
=
⋅
=
⋅
×
=
∆
→
=
=
∆
⋅
∆
=
−
−
−
−
E E
m m
c m E c N =
lucht m S H mmol 42 , S 0 H mol 10 158 ,
4 ⋅ −4 2 = 2 3
Opgave 1.22 Grote en kleine getallen in een stof.
1 gram water ( 1 mL) bevat 3,346·1022 moleculen H2O.
Water heeft bij 4 °C een dichtheid van 1000 kg/m3. IJs heeft bij 0 0C een dichtheid 920 kg/m3 .
Waterdamp in de lucht heeft bij 20 0C en een relatieve vochtigheid van 60% een dichtheid van 10,2 g/m3.
a Bereken het aantal watermoleculen in 1 gram ijs.
1 gram ijs = 1 gram water = 3,346·1022 moleculen H2O b Bereken het aantal watermoleculen in 1 gram waterdamp.
1 gram waterdamp = 1 gram water = 3,346·1022 moleculen H2O c 1 liter water = 1000 gram = 3,346∙1025 moleculen H2O
d 1 liter ijs = 920 gram = 920 × 3,346∙1022 = 3,078∙1025 moleculen H2O
e In 1 liter water zitten meer moleculen dan in 1 liter ijs.
In 1 liter water zit × 920
1000 meer moleculen dan in 1 liter ijs f In 1 liter lucht van 200C en 60% vochtigheid zit 10,2 gram water.
23 22 3,41 10 10
346 , 3 2 , 10 g 2 ,
10 = × ⋅ = ⋅ moleculen H2O
g In 1 liter lucht van 200C en 100% vochtigheid zit 10,2 17g 60
100× = water.
23 22 5,69 10 10
346 , 3 17 g
17 = × ⋅ = ⋅ moleculen H2O h De waarde bij g is = ×
3 5 60
100 groter dan die bij f.
i 3,346·1022 moleculen = 1 g
kg 10 99 , 10 2 346 , 3 molecuul 1
1 22 = ⋅ −23
= ⋅
j Een watermolecuul heeft een diameter van ongeveer 0,3 nm.
In 1 m passen 9 3,33 109 10
3 , 0
1 = ⋅
⋅ − moleculen
Opgave 1.23 Atoomkern splijten.
J 10 865 , 6 s) 10 m 9979 , 2 ( kg 10 638 , 7 ) atoom per (
kg 10 638 , 7 kg 10 6605 , 1 0046 , 0
u 0,0046 u)
0026 , 4 u (234.0436 -
u 0508 , 238
13 2
8 30
30 27
2
−
−
−
−
⋅
=
⋅
×
⋅
=
⋅
=
⋅
×
=
∆
→
= +
=
∆
⋅
∆
=
E m m
c m E
J 10 75 , 1 ) 1 ( :
J 10 794 , 1 J 10 865 , 6 10 613 , 2 ) 1 (
U atomen 10
613 , 2
U atomen 10
022 , 238 6 U 1
238 mol 1
9
9 13
21 238 21
238 23
238
⋅
=
⋅
=
⋅
×
⋅
=
⋅
=
→
⋅
×
=
→
=
−
gram per
E afgerond
gram per
E N
N n
2 2
2
μm 135 μm 2 μm 5 , 7 π ) μm 75 , 3 ( π 2
π π
2
=
×
× +
×
×
=
→
⋅
⋅ +
⋅
×
= A
h d r
A
s ery' 10 0 , 3 10 29,7 10
4 , 5 5 , 5 liter 5 , 5
s ery' 10 5,4 bloed L 1 s ery' 10 4 , 5 bloed mL 1
13 12
12
12 9
×
=
×
=
⋅
×
=
→
⋅
=
→
⋅
=
2 12
12 2 12
m 4000 10
135 10 7 , 29 ) s ery' alle (
m 10 135 ) ery 1 (
=
×
×
×
=
→
⋅
=
−
−
A A
L 2 , 5 ) bloed ( dan ) s ery' ( 2 ) bloed ( Als
L 6 , 2 m 10 6 , 2 10 88 10 7 , 29 ) s ery' alle (
m 10 88 ) ery 1 (
3 3 18
12 3 18
=
×
=
=
⋅
=
×
×
×
=
→
⋅
=
−
−
−
V V
V A V
mmolmL 10
1 , 1 :
mmol 10
076 , 1 moleculenmmol
10 022 , 6
moleculen 10
48 , bloed 6
mL 1
moleculen 10
48 , 6 10 2 , 1 10 4 , 5 bloed mL 1
s ery' 10 4 , 5 bloed mL 1
2
2 20
18
18 9
9 9
−
−
⋅
=
−
⋅
=
⋅
= ⋅
→
⋅
=
⋅
×
⋅
=
→
⋅
=
gehalte e
hemoglobin afgerond
e hemoglobin
e hemoglobin
mL 173mg
mmol 16114mg
mmolmL 10
076 ,
1 ⋅ 2 × =
=
−gehalte −
e hemoglobin Opgave 1.24 Radioactief verval.
a
b
Opgave 1.25 Rode bloedcellen (ery’s)
a V =π⋅r2⋅h→V =π×(3,75μm)2×2μm=88μm3 b
c
d
e
f s
s ery' 10 9 , 2 s 3600 24 120
s ery' 10 dagen 3
120 in s ery' 10 3
13 6
13 = ⋅
×
×
→ ⋅
⋅
g 5 10 ery's
m 10 2
m m 1
1 in aantal m
10
2 6 -6 = ⋅ 5
= ⋅
→
⋅
= −
d
Opgave 1.26 Hemoglobinegehalte in het bloed.
a
b
mL 4mg , mmol 2 56mg
mmolmL 10
304 , 4 ) Fe (
mmolmL 10
304 , 4 10 076 , 1 4 ) atomen Fe
(
2
2 2
=
×
⋅
=
→
⋅
=
⋅
×
=
−
−
−
−
m n
15 7
23 2
23 23
3 3
3 3
7 9
2
10 84 , 10 3 2,82
10 cm 1,08
1 van laagje per C atomen aantal
C atomen 10
08 , 1 10 022 , 6 18 , 0 ) 1 (
C mol 18 , 0 mol 12g
g 16 , ) 2 cm 1 (
g 16 , 2 ) 1 ( kg 16 , 2 ) dm 1 (
10 82 , 10 2 335 , 0
10 335
, 0 1 1
⋅
⋅ =
= ⋅
→
⋅
=
⋅
×
=
→
=
=
→
=
→
=
⋅
⋅ =
=
= −
−
cm N n
cm m m
m nm
cm cm in laagjes aantal
` c
Opgave 1.27 Grafeen, bijzonder materiaal.
a 9 6
3
10 82 , 10 2 335 , 0
10 335
, 0
1 1 = ⋅
= ⋅
= −
− m
nm mm mm
in laagjes aantal
b
c Zie uitwerking bij b)