# Can I get some help please? Thanks!

Aug 21, 2017

1086 mm Hg

#### Explanation:

Using the slope method

The change in pressure per degree C
${20}^{o} C - {10}^{o} C = {10}^{o} C$
$750 - 726 = \frac{24}{10} = \frac{2.4 m m H g}{1} ^ o C$

The change in pressure per degree C second interval

 40^o C - 20^oC = 20^oC

$800 - 750 = \frac{50}{20} = \frac{2.5 m m H g}{1.0} ^ o C$

The change in pressure per degree C third interval

$880 - 800 = \frac{80}{30} = \frac{2.6 m m H g}{1.0} ^ o C$

The change in pressure per degree C fourth interval

960- 880 = 80/30 = (2.6mm Hg)/1^oC

averaging the change in pressure for the four intervals

$\frac{2.4 + 2.5 + 2.6 + 2.6}{4} = 2.525$

The change in temperature 150-100 = 50 so

${50}^{o} C \times \frac{2.525 m m H g}{1} ^ 0 C = \left(126.25 m m H g\right)$

Adding this change in pressure to the value of 960 gives

960 + 126 = 1086 mmHg.

this is an approximate value as the the intervals do not give a perfect straight line slope.

Aug 21, 2017

I get $p = \text{1089 mmHg}$

#### Explanation:

I would use Excel or a graphing calculator to plot a graph of $p$ vs. $t$ and get an equation for the line of best fit.

I don’t have a graphing calculator, so I plotted the data in Excel.

Excel told me that the equation of the best-fit line was

$y = 2.608 x + 698.01$ or

$p = 2.608 t + 698.01$

Substituting $t = \text{150 °C}$, I get

p = (2.608 × 150 + 698.01)color(white)(l)"mmHg" = "(391.2 + 698.01) mmHg" = "1089 mmHg"