Question

1-4 review and reinforcement
units of measurement
answer each of the following questions in the space provided.

1. explain the usefulness of the international system of units to scientists.
2. if a chemist performed an experiment in spain, how could she be sure that chemists in china could interpret the measurements she obtained?
3. list the si base units.
4. give two examples of derived units. include the units of measurement.

match the following si base units with the physical quantities they measure. write the letter on the line.

1. kilogram a. length
2. meter b. electric current
3. second c. mass
4. kelvin d. temperature
5. mole e. time
6. ampere f. quantity, count

match the following derived units with the units in which they are expressed. write the letter on the line.

1. area a. n
2. volume b. pa
3. pressure c. m²
4. force d. m³
5. energy e. j

Explanation:

1. The International System of Units (SI) provides a standardized, universal language for scientists. It ensures accuracy, reproducibility, and easy communication of measurements globally.
2. By using the SI units in her experiment, the chemist ensures that measurements are in a common - understood format. SI units are recognized worldwide, so Chinese chemists can interpret them easily.
3. The SI base units are meter (length), kilogram (mass), second (time), ampere (electric current), kelvin (temperature), mole (amount of substance), and candela (luminous intensity).
4. Examples of derived units are the newton (N) for force, where 1 N = 1 kg·m/s², and the pascal (Pa) for pressure, where 1 Pa=1 N/m².

5 - 10: kilogram - c (mass), meter - a (length), second - e (time), kelvin - d (temperature), mole - f (quantity, count), ampere - b (electric current).
11 - 15: area - c (m²), volume - d (m³), pressure - b (Pa), force - a (N), energy - e (J).

Answer:

1. The International System of Units provides a universal, standardized way for scientists to communicate measurements, ensuring accuracy and reproducibility of experiments across the world.
2. By using the International System of Units (SI) in her experiment, as SI units are internationally recognized and understood.
3. Meter (length), kilogram (mass), second (time), ampere (electric current), kelvin (temperature), mole (amount of substance), candela (luminous intensity).
4. Newton (N) for force (1 N = 1 kg·m/s²), Pascal (Pa) for pressure (1 Pa = 1 N/m²).
5. c
6. a
7. e
8. d
9. f
10. b
11. c
12. d
13. b
14. a
15. e