Indietro
Problema 33b
The following statements pertain to the development of the theory of the structure of DNA. Match the statement with the appropriate step (observation, hypothesis, experiment designed to test hypothesis) in the scientific method. (b) In a sample of DNA, there are equal amounts of the bases A and T and equal amounts of the bases C and G.
Problema 33c
The following statements pertain to the development of the theory of the structure of DNA. Match the statement with the appropriate step (observation, hypothesis, experiment designed to test hypothesis) in the scientific method. (c) Direct X rays at a sample of crystallized DNA, and inter-pret the diffraction pattern for structural information.
- Label the following statements about the world's largest gold bar as quantitative or qualitative observations. (This gold bar was worth approximately $10.25 million in 2013.) (a) The melting point of gold is 1064.2 °C. (b) The volume of the gold bar is 15,730 cm3. (c) Gold metal is a conductor of electricity. (d) The mass of the gold bar is 250 kg. (e) The gold bar is yellow and shiny
Problema 34
- Refer to Figure 1.2. What is developed when numerous observations support a hypothes
Problema 36
- What is the difference between a hypothesis and theory? (a) A hypothesis provides an explanation for a phenomenon, but a theory does not. (b) A theory provides an explanation for a phenomenon, but a hypothesis does not. (c) Both a theory and a hypothesis provide an explanation for a phenomenon, but a theory has been upheld by experi-mental observations
Problema 37
Problema 38a
What SI units are used for measuring the following quanti-ties? For derived units, express your answers in terms of the six fundamental units. (a) Mass
Problema 38b
What SI units are used for measuring the following quanti-ties? For derived units, express your answers in terms of the six fundamental units. (b) Length
Problema 38c
What SI units are used for measuring the following quanti-ties? For derived units, express your answers in terms of the six fundamental units. (c) Temperature
Problema 38d
What SI units are used for measuring the following quanti-ties? For derived units, express your answers in terms of the six fundamental units. (d) Volume
Problema 38e
What SI units are used for measuring the following quanti-ties? For derived units, express your answers in terms of the six fundamental units. (e) Energy
Problema 38e
What SI units are used for measuring the following quanti-ties? For derived units, express your answers in terms of the six fundamental units. (e) Energy
Problema 38f
What SI units are used for measuring the following quanti-ties? For derived units, express your answers in terms of the six fundamental units. (f) Density
- Complete the following equivalent expressions by filling in the blanks. (a) 1 km = ____ m (b) 1m = _____ km (c) 1 mmol = _____ mol (d) 1 mol = _____ mmol
Problema 40
- Bottles of wine sometimes carry the notation 'Volume = 75 cL. What does the unit cL mean?
Problema 42
- Which quantity in each of the following pairs is larger? (a) 5.63 * 106 cm or 6.02 * 101 km
Problema 43
- Which quantity in each of the following pairs is smaller? (c) 2.9 GA or 3.1 * 1015 mA
Problema 44
- How many microliters are in 1 L? In 20 mL?
Problema 46
Problema 47a
Carry out the following conversions. (a) 5 pm = _____ cm = _____ nm
Problema 47b
Carry out the following conversions. (b) 8.5 cm^3 = _____ m^3 = _____ mm^3
Problema 47c
Carry out the following conversions. (c) 65.2 mg = _____ = g = _____ pg
Problema 48a
Express the following measurements in scientific notation. (a) 453.32 mg
Problema 48b
Express the following measurements in scientific notation. (b) 0.000 042 1 mL
- Convert the following measurements from scientific notation to standard notation. (a) 3.221 * 10-3 mm (b) 8.940 * 105 m (c) 1.350 82 * 10-12 m3 (d) 6.4100 * 102 km
Problema 49
- An experimental procedure call for 250 mg of calcium car-bonate. The balance in the laboratory measures mass in grams and reads to four decimal places. Which reading on the bal-ance corresponds to 250 mg? (a) 0.0250 (b) 0.2500 (c) 0.0025
Problema 50
- A virus has a diameter of 5.2 * 10-8 m. What is the most appropriate prefix for reporting the diameter of the virus?
Problema 51
- The estimated concentration of gold in the oceans is 1.0 * 10^-11 g/mL. (b) Assuming that the volume of the oceans is 1.3 * 10^21 L, estimate the amount of dissolved gold in grams in the oceans.
Problema 53
- The normal body temperature of a goat is 39.9 °C, and that of an Australian spiny anteater is 22.2 °C. Express these tem-peratures in degrees Fahrenheit.
Problema 54
- Of the 90 or so naturally occurring elements, only four are liquid near room temperature: mercury (melting point = -38.87 °C), bromine (melting point = -7.2 °C), cesium (melting point = 28.40 °C), and gallium (melting point = 29.78 °C). Convert these melting points to degrees Fahrenheit.
Problema 55
- Suppose that your oven is calibrated in degrees Fahrenheit but a recipe calls for you to bake at 175 °C. What oven set-ting should you use?
Problema 56
- Tungsten, the element used to make filaments in light bulbs, has a melting point of 6192 °F. Convert this temperature to degrees Celsius and to kelvin.
Problema 57