Convert the following pressures into atmospheres. a. 105.2 kPa b. 75.2 cm Hg c. 752 mm Hg d. 767

Convert the following pressures into atmospheres. a. 105.2...

Key Concepts

Unit Conversion

Unit conversion involves changing a measurement from one unit to another using conversion factors. This process is crucial when comparing or combining measurements expressed in different units to ensure consistency and accuracy.

Pressure

Pressure is the force applied over a given area. It is a fundamental physical quantity measured in different units such as pascals, kilopascals, torr, and atmospheres, which are used depending on the context of the application.

Standard Atmosphere

A standard atmosphere is a unit of pressure defined as 101.325 kilopascals. It is used as a reference value in many scientific and engineering calculations, and is also equivalent to about 760 torr or 760 millimeters of mercury.

Dimensional Analysis

Dimensional analysis is a method used to convert between different units of measurement by applying conversion factors systematically. This technique helps maintain the correctness of units throughout the calculation process and is essential in solving problems involving unit conversions.

Transcript

00:01 In this video, we will be reviewing unit conversions between different units of pressure.

00:06 In this case, we are given four different problems, each with a different unit of pressure.

00:12 We have kilopascals, centimeters of mercury, millimeters of mercury, and lastly, tor.

00:20 And in each case, we're asked to convert these units into units of atmosphere, atm.

00:27 So to start off, we have 105 .2 kilopascals.

00:30 Now we don't know how many kilopascals is equal to, or how many atmospheres is equal to one kilopascal.

00:40 But we can convert kilopascal into pascal, which is a more familiar unit.

00:47 What we'll be doing is we can use a unit conversion box.

00:50 And inside this box, all of the values in the numerator and the denominator are equal to one.

00:58 Meaning that if we want to cancel out kilopascals, we put that in the denominator, and we want pascal's.

01:10 So we'll just put pascal's in the numerator.

01:15 Now, one kilopascal is equal to 1 ,000 pascal.

01:21 So even though this fraction has different units in the numerator and denominator, the values are equivalent to 1.

01:29 The kilopascals cancel out.

01:33 And we're left with pascal's.

01:36 Once we multiply this through, we get 1 ,000, 200, pascal's.

01:51 Now we still want pascal's in the unit of atmosphere.

01:55 So now we're going to write another unit conversion box, and we know that one atmosphere, now since we want atmosphere, we're going to put that in the numerator, we know that one atmosphere is equal to 1001, 325 pascal.

02:26 Since pascal is in the denominator, it cancels out, and we are left with the fraction 1 ,500, all in the unit atm now, over 1 ,1 ,325.

02:59 Now once we divide this, we get 1 .0 .0 .0 .0 .0 .0.

03:12 I'm going to put this answer box in blue.

03:19 That way we don't confuse it with our unit conversion box.

03:24 So we know 105 .2 kilopascal is equal to 1 .04 atm.

03:31 In number two, we have 75 .2 centimeters mercury.

03:36 Once again, we don't know how to convert centimeters mercury directly to atm.

03:41 So we're going to convert to a unit that's more familiar...