Question

exam lesson name: states of matter
exam number: 700698rr
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question 15 of 20 :
select the best answer for the question.

1. whats the absolute pressure if the gauge pressure of a gas is 114 kpa?

○ a. 14 kpa
○ b. 220 kpa
○ c. 214 kpa
○ d. 50 kpa

Explanation:

Step1: Recall absolute pressure formula

Absolute pressure ($P_{abs}$) is the sum of gauge pressure ($P_{gauge}$) and atmospheric pressure ($P_{atm}$). Standard atmospheric pressure is approximately $100\ \text{kPa}$ (or more precisely, around $101.3\ \text{kPa}$, but for simplicity in some contexts, $100\ \text{kPa}$ or $101.3\ \text{kPa}$ can be used. Here, using $100\ \text{kPa}$ as an approximation, but let's check with the options. Wait, actually, standard atmospheric pressure is about $101.3\ \text{kPa}$, but maybe in the problem's context, they use $100\ \text{kPa}$? Wait, no, let's calculate properly. The formula is $P_{abs}=P_{gauge} + P_{atm}$. The standard atmospheric pressure is approximately $101.3\ \text{kPa}$, but maybe in the problem, they use $100\ \text{kPa}$? Wait, no, let's see the options. The gauge pressure is $114\ \text{kPa}$. So if we take $P_{atm}=100\ \text{kPa}$ (maybe a rounded value for the problem), then $P_{abs}=114 + 100 = 214\ \text{kPa}$. Wait, or if $P_{atm}=101.3$, then $114 + 101.3 = 215.3$, but the option C is $214$, which is close. So probably, the problem uses $P_{atm}=100\ \text{kPa}$ for simplicity. So:

Step2: Calculate absolute pressure

Given $P_{gauge}=114\ \text{kPa}$, $P_{atm}\approx 100\ \text{kPa}$ (or $101.3$, but the option is $214$, so $114 + 100 = 214$? Wait, no, $114 + 100 = 214$? Wait, $114 + 100 = 214$? Yes. Wait, but standard atmospheric pressure is $101.3$, but maybe the problem rounds it to $100$? Or maybe I made a mistake. Wait, let's check the options. Option C is $214$, which is $114 + 100$. So:

$P_{abs}=P_{gauge} + P_{atm}$

Assuming $P_{atm}=100\ \text{kPa}$ (maybe the problem's context), then:

$P_{abs}=114\ \text{kPa} + 100\ \text{kPa} = 214\ \text{kPa}$

Answer:

C. 214 kPa