‘Convert the pressure 1.30 atm to kPa:’
The Correct Answer and Explanation is:
Correct Answer:
To convert 1.30 atm to kilopascals (kPa):1 atm=101.325 kPa1 \, \text{atm} = 101.325 \, \text{kPa}1atm=101.325kPa1.30 atm×101.325 kPa/atm=131.7225 kPa1.30 \, \text{atm} \times 101.325 \, \text{kPa/atm} = 131.7225 \, \text{kPa}1.30atm×101.325kPa/atm=131.7225kPa
Final Answer:1.30 atm=131.72 kPa(rounded to 2 decimal places)1.30 \, \text{atm} = \boxed{131.72 \, \text{kPa}} \quad \text{(rounded to 2 decimal places)}1.30atm=131.72kPa(rounded to 2 decimal places)
Textbook-Style Explanation:
In chemistry and physics, pressure is a fundamental concept that measures the force exerted per unit area. It can be expressed in various units, including atmospheres (atm), pascals (Pa), millimeters of mercury (mmHg), and kilopascals (kPa). Understanding how to convert between these units is essential when working with gas laws and thermodynamic equations.
One standard unit of pressure is the atmosphere (atm), which was originally based on the average atmospheric pressure at sea level. However, in scientific contexts, the kilopascal (kPa) is often preferred because it aligns with the International System of Units (SI).
The conversion factor between atmospheres and kilopascals is derived from the definition:1 atm=101.325 kPa1 \, \text{atm} = 101.325 \, \text{kPa}1atm=101.325kPa
This means that every atmosphere of pressure is equivalent to 101.325 kilopascals. To convert from atm to kPa, multiply the pressure in atmospheres by this conversion factor.
In this example, we are asked to convert 1.30 atm to kPa. Applying the conversion:1.30×101.325=131.7225 kPa1.30 \times 101.325 = 131.7225 \, \text{kPa}1.30×101.325=131.7225kPa
For most practical purposes, especially when reporting measurements in scientific contexts, it is customary to round the result to a reasonable number of significant figures. Here, rounding to two decimal places gives:131.72 kPa131.72 \, \text{kPa}131.72kPa
This conversion is useful in gas law calculations involving the ideal gas law (PV = nRT), where pressure must be consistent with the other units used for volume, temperature, and the gas constant. Mastery of unit conversions ensures accurate and consistent results in experimental and theoretical work.
