A student heated a mixture of iron filings and sulfur strongly. He saw a red glow spread through the mixture as the reaction continued. At the end of the experiment a black solid had been formed. a....

A car crashes head-on into a brick wall. Use the idea of inertia to explain why the driver is more likely to come out through the windscreen if he or she is not wearing a seat belt.

Estimate the mass and weight of each of the following at the surface of the Earth: a. A kilogram of potatoes b. An average student c. A mouse d. A 40-tonne truck. (For estimates, use g = 10 m s 2 ; 1...

Use the kinetic theory to explain the following: a. When you take a block of butter out of the fridge, it is quite hard. However, after 15 minutes it is soft enough to spread. b. When you come home...

A rocket has a mass of 5,000 kg. At a particular instant, the resultant force acting on the rocket is 200,000 N. Calculate its acceleration.

An athlete competing in the long jump leaves the ground with a velocity of 5.6 m s 1 at an angle of 30 to the horizontal. a. Determine the vertical component of the velocity and use this value to...

A solid plastic sphere falls towards the Earth. The diagram below shows the speed-time graph of the fall up to the point where the sphere hits the Earth's surface. a. Describe in detail the motion of...

Emissions from a radioactive source pass through a hole in a lead screen and into a magnetic field, as shown in the diagram. Radiation detectors are placed at A, B and C. They give the following...

Name these forces: a. The upward push of water on a submerged object b. The force that wears away two surfaces as they move over one another c. The force that pulled the apple off Isaac Newtons tree...

Copy and complete the table below, which summarises some of the functional categories into which proteins can be placed. Category Example structural 1. 2. enzyme insulin haemoglobin and myoglobin...

Calculate how much work is done by a 50 kW car engine in a time of 1.0 minute.

a. Copy the following table to summarise some differences between collagen and haemoglobin. Collagen Haemoglobin Use the following to guide you. Row 1: State whether globular or fibrous. Row 2: State...

The diagram below shows an enzyme and two inhibitors of the enzyme, X and Y. Which of the following describes the two inhibitors? A. X and Y are competitive inhibitors. B. X and Y are non-competitive...

The graph shows the progress of the digestion of starch by the enzyme salivary amylase. Why does the reaction slow down? A. End-product inhibition by maltose. B. The salivary amylase is becoming...

If methylene blue dye is added to a suspension of yeast cells, living cells do not take up the stain, and they remain colourless. However, dead cells are stained blue. This fact was used to carry out...

A balloon of volume 3000 m 3 is filled with hydrogen of density 0.090 kg m 3 . The mass of the fabric of the balloon is 100 kg. Calculate the greatest mass that the balloon can lift in air of density...

a. Identify the fragments that would cause peaks in the mass spectrum of HOCH 2 COCH 3 with the following m/e values: i. m/e = 15 ii. m/e = 17 iii. m/e = 31 iv. m/e = 43 v. m/e = 57 vi. m/e = 59 b....

a. By how many degrees does the angular displacement of the hour hand of a clock change each hour? b. A clock is showing 3.30. Calculate the angular displacements in degrees from the 12.00 position...

In each of the following cases, state what provides the resultant force causing centripetal acceleration: a. The Moon orbiting the Earth b. A car going round a bend on a flat, rough road c. The...

A string orchestra consists of 15 violins, 8 violas, 7 cellos and 4 double basses. A chamber orchestra consisting of 8 violins, 4 violas, 2 cellos and 2 double basses is to be chosen from the string...

Mars orbits the Sun once every 687 days at a distance of 2.3 10 11 m. The mass of Mars is 6.4 10 23 kg. Calculate: a. The average speed in metres per second b. Its centripetal acceleration c. The...

Explain why it is impossible to whirl a bung around on the end of a string in such a way that the string remains perfectly horizontal.

a. Find the values of i. 7 P 3 ii. 9 P 4 iii. 10 P 8 b. Find the values of i. 7 C 3 ii. 9 C 4 iii. 10 C 8 c. Show that, for the values of n and r in parts a and b, n C r = n P r /r!.

A vessel of volume 0.20 m 3 contains 3.0 10 26 molecules of gas at a temperature of 127 C. Calculate the pressure exerted by the gas on the vessel walls.

Give all answers to 3 significant figures. Ammonium nitrate decomposes on heating to give nitrogen(I) oxide and water as follows: NH 4 NO 3 (s) N 2 O(g) + 2H 2 O(l) a. What is the formula mass of...

a. i. What do you understand by the term relative atomic mass? ii. A sample of boron was found to have the following % composition by mass: Calculate a value for the relative atomic mass of boron....

a. What do you understand by the term atomic orbital? b. Draw diagrams to show the shape of: i. An s orbital ii. A p orbital. c. Element x has the electronic configuration 1s 2 2s 2 2p 6 3s 2 3p 6 3d...

A capacitor has a potential difference of 6.0 V across its plates and stores 9.0 mJ of energy. Which row in the table gives the capacitance of the capacitor and the charge on its plates? Capacitance...

Explain the following differences in terms of the type of bonding present. a. Aluminium oxide has a melting point of 2980 C but aluminium chloride changes to a vapour at 178 C. b. Magnesium chloride...

Propanone is a liquid. It has the structure The equation for the complete combustion of propanone is: CH 3 COCH 3 (l) + 4O 2 (g) 3CO 2 (g) + 3H 2 O(l) a. Use the following bond energies (in kJ mol 1...

The luminosity of the star Aldebaran is 520 times that of the Sun. The wavelength of light at peak intensity for Aldebaran is 740 nm and the wavelength of light at peak intensity for the Sun is 500...

a. Define standard enthalpy change of combustion. b. When red phosphorus burns in oxygen the enthalpy change is 2967 kJ mol 1 . For white phosphorus the enthalpy change is 2984 kJ mol 1 . For both...

a. Calculate the energy transferred when the temperature of 75 cm 3 of water rises from 23 C to 54 C. b. When 8 g of sodium chloride is dissolved in 40 cm 3 of water the temperature falls from 22 C...

a. Define standard enthalpy change of formation. b. Calculate the standard enthalpy change of formation of methane from the following standard enthalpy changes of combustion: carbon = 394 kJ mol 1...

A particle is projected from horizontal ground with initial speed 15 m -1 and angle of elevation 60. Find the horizontal distance travelled when the particle is first at a height of 8m above ground...

a. In each of the following equations, state which reactant has been oxidised: i. PbO + H 2 Pb + H 2 O ii. CO + Ag 2 O 2Ag + CO 2 iii. 2Mg + CO 2 2MgO + C b. In each of the following equations,...

A particle is projected from a platform 4m above horizontal ground, with an initial speed of 20 ms -1 and an angle of elevation of 20. Find the direction of the particle as it lands on the ground.

In a study of the XSORT gender selection method developed by the Genetics & IVF Institute, 945 couples given treatment had 66 baby boys and 879 baby girls.

A researcher measures the braking reaction time of a subject and records a value of 2.4 seconds, but the subjects actual braking reaction time is 1.9 seconds. What is the absolute error?

Police set up a sobriety checkpoint at which every fifth driver is stopped and interviewed.

A New York Times editorial criticized a chart caption that described a dental rinse as one that reduces plaque on teeth by over 300%. If the dental rinse removes all of the plaque, what percentage is...

Before taking off, a pilot is supposed to set the aircraft altimeter to the elevation of the airport. A pilot leaves from Denver (altitude 5280 feet) with her altimeter set to 2500 feet. Explain how...

a. State what is meant by: i. A perfectly elastic collision ii. A completely inelastic collision. b. A stationary uranium nucleus disintegrates, emitting an alpha-particle of mass 6.65 10 27 kg and...

Look at Figure 29.28. a. Calculate the relative molecular mass of leucine enkephalin (C 28 H 37 N 5 O 7 ) using relative atomic masses. (A r values C = 12.0, H = 1.0, N = 14.0, O = 16.0) b. i. How is...

Look at Figure 29.27. a. What is the retention time of the compound shown? b. What is the approximate relative molecular mass of the compound shown? c. How would the compound be identified? 100 200...

In a Gallup poll of 1038 adults, 5% of the respondents said that second-hand smoke is not at all harmful. How many respondents said that second-hand smoke is not at all harmful?

ZIP codes are quantitative data because, in general, lower numbers are in the east and higher numbers are in the west. Does It Make Sense? For Exercises, determine whether the statement makes sense...

Braking reaction times of 36 randomly selected licensed drivers are measured and 20 of them are greater than 1.9 seconds. What is the percentage of reaction times greater than 1.9 seconds?

a. Look back to Figure 29.18. The high resolution NMR spectrum shown is from a sample of ethanol containing traces of water. How would the NMR spectrum differ if D 2 O had been added to the sample of...

This diagram shows part of the track of a roller-coaster ride in which a truck loops the loop. When the truck is at the position shown, there is no reaction force between the wheels of the truck and...

This diagram shows a toy of mass 60 g placed on the edge of a rotating turntable. a. The radius of the turntable is 15.0 cm. The turntable rotates, making 20 revolutions every minute. Calculate the...

The International Space Station (Figure 16.12) has a mass of 350 tonnes, and orbits the Earth at an average height of 340 km where the gravitational acceleration is 8.8 m s 2 . The radius of the...

You will need the following data to answer the following questions. (You may take the charge of each sphere to be situated at its centre.) 0 = 8.85 10 12 F m 1 A metal sphere of radius 20 cm carries...

a. Define the term capacitance of a capacitor. b. This is a circuit that can be used to measure the capacitance of a capacitor. The reed switch vibrates back and forth at a frequency of 50 Hz. Each...

a. Show that the capacitance C of an isolated conducting sphere of radius r is given by the formula: C = 4 0 r This diagram shows two identical conducting brass spheres of radius 10Cm mounted on...

The spherical dome on a Van de Graaff generator has a diameter of 40 cm and the potential at its surface is 5.4 kV. a. i. Calculate the charge on the dome. ii. Calculate the capacitance of the dome....

a. State one use of a capacitor in a simple electric circuit. b. This is a circuit used to investigate the discharge of a capacitor, and a graph showing the change in current with time when the...

When we refer to a normal distribution, does the word normal have the same meaning as it does in ordinary usage? Explain.

Do you think that comparisons of SAT scores over 2 years are meaningful? Over 10 years? Do you agree that the long-term trends indicate that students today have poorer verbal skills but better...

Briefly explain a major reason why the Central Limit Theorem is useful in statistics.

The distribution of incomes of adults is a right-skewed distribution. Therefore, if we select many samples of 64 incomes at random from this distribution, the means of these samples will also have a...

The percentage of the worlds population living in developed countries decreased from 27.1% in 1970 to 16.4% now. Percentages of Percentages. Exercises describe changes in which the measurements...

Types of movies (drama, comedy, etc.) Levels of Measurement. For the data described in Exercises, identify the level of measurement (nominal, ordinal, interval, or ratio).

Find an example of a stack plot in a recent news report. Comment on the effectiveness of the display. Could another display have been used to depict the same data?

The following data show the body temperatures (in F) of randomly selected subjects who were not ill at the time. Construct a frequency table with seven bins:96.997.2, 97.397.6, 97.798.0, and so on....

List the relative frequencies that correspond to the given frequencies. Pulse Rates of Females. In Exercises, refer to the following frequency table of pulse rates of a sample of females. Pulse rate...

The stack plot in Figure 3.25 shows the numbers of bachelors degrees awarded to males and females since 1970. The last few years are projections. a. Estimate the numbers of bachelors degrees to be...

List the relative frequencies that correspond to the given frequencies.

The graph in Figure 3.21 shows home prices in different regions of the United States. a. Describe general trends that apply to the home price data for all regions. b. Describe any differences that...

In a survey conducted by Kelton Research, 1004 adults were asked to identify the sounds that they find most annoying. In response, 279 chose jackhammers, 388 chose car alarms, 128 chose barking dogs,...

How many females are represented in the frequency table? How many categories are in the frequency table? Pulse rate (beats per minute) 50-59 60-69 70-79 80-89 90-99 100-109 Frequency 17 33 41 37 13 4

Children living near a smelter in Texas were exposed to lead, and their IQ scores were subsequently measured. The following histogram was constructed from those IQ scores. Figure 3.11 a. Estimate the...

Theres been only a very slight rise in our stock price over the past few months, but I wanted to make it look dramatic so I started the vertical scale from the lowest price rather than from zero....

I drew a map on which I scaled the lengths (from east to west) of different counties based on their numbers of family-owned farms, and found that a county with twice as many farms as another ended up...

What is the purpose of binning? Give an example for which binning is useful.

The numbers 12, 74, 77, 76, 73, 78, 88, 19, 9 23, and 25 were sewn on the jerseys of the starting offense for the New Orleans Saints when they won a Super Bowl football game. Complete Classification....

What is the gamblers fallacy? Give an example

Figure 5.10 on the next page shows a histogram for the departure delay times (in minutes) of 152 American Airlines flights from Los Angeles to San Francisco. Is this distribution close to normal?...

A medical researcher wants to test the claim that healthy adults have a mean body temperature less than 98.6F.

A 0.5002-g sample that assayed 96.4% Na 2 SO 4 required 48.63 mL of a barium chloride solution. Reaction: Calculate the analytical molar concentration of BaCl 2 in the solution. Ba?+ + So,?- BaSO4(s)

The hydrogen sulfide in a 40.0-g sample of crude petroleum was removed by distillation and collected in a solution of CdCl 2 . The precipitated CdS was then filtered, washed, and ignited to CdSO 4 ....

There were 1,038,280 bankruptcy cases filed last year, and in the year 2000 there were 1,276,900 bankruptcy cases filed Relative Change. Exercises each provide two values. For each pair of values,...

You receive a Visa credit card bill for $512.50, but it includes a charge of $8.00 that was not valid. (That is, the true credit card bill should be $8.00 less than the bill claims.)

If you spent $14,222 for goods, services, and housing in 1985, what would the same purchases have cost in 2010? Consumer Price Index. In Exercises, use the Consumer Price Index values from Table 2.2....

In 2005, the average price of electricity was 10.0 cents per kWh (kilowatt-hour), and in 2015, the average price was 13.8 cents per kWh. Compare the increase in the price of electricity to the...

If you spent $2.90 for a pound of coffee in 2005, what would the price have been in 2015? Coffee Index. In Exercises, use the following table of index numbers based on the price of a pound of coffee....

The arrival delay times recorded for a random sample of flights from New York to Chicago. Discrete or Continuous. In Exercises, state whether the data described are discrete or continuous, and...

A quality control engineer wants to draw attention to the car parts that require repair most often, so she uses a Pareto chart to illustrate the frequencies of repairs for the various car parts. Does...

Births at a hospital in New York State occurred on the different days of the week (in the order Monday through Sunday) with these frequencies: 52, 66, 72, 57, 57, 43, 53. Construct a frequency table...

A statistics professor with too much time on his hands weighed each M&M candy in a bag of 465 plain M&M candies. a. One of the 465 M&Ms weighed 0.776 gram and it was heavier than 25 of the other...

One result of the NAEP reading tests is that students in private schools tend to score significantly higher than students in public schools. Does this imply that private schools are better than...

Distinguish between the distribution of sample means and distribution of sample proportions.

Using sample data on footprint lengths and heights from men, the equation of the best-fit line is obtained, and it is used to find that a man with a footprint length of 36 inches is predicted to have...

Although Nielsen surveys only a few thousand households out of the millions that own TVs, they have a good chance of getting an accurate estimate of the proportion of the population watching the...

For a random sample of 575 randomly selected car batteries, it was found that their output had a mean of 12.2volts and a standard deviation of 1.4 volts.

What is a probability distribution? Briefly describe a format that is used to display a probability distribution.

Distinguish between a distribution of sample means and a distribution of sample proportions.

What is a two-way table? What are the entries in its cells?

A random sample of 64 newborn girls is obtained and they have a mean birth weight of 3390 grams. What is the probability of randomly selecting another 64 newborn girls and getting a mean birth weight...

In a two-way table, all of the observed frequencies are lower than the expected frequencies, so the x 2 statistic is negative.