Question

missed this? read section 11.3. you can click on the review link to access the section in your etext. convert each measurement to atm. part a 923 torr express your answer in atmospheres to three significant figures. part b 4.6×10⁴ pa express your answer in atmospheres to two significant figures.

Explanation:

Part A:

Step1: Recall conversion factor

We know that \( 1\ \text{atm} = 760\ \text{torr} \). So to convert torr to atm, we use the formula \( P(\text{atm})=\frac{P(\text{torr})}{760} \).

Step2: Substitute the value

Given \( P = 923\ \text{torr} \), then \( P(\text{atm})=\frac{923}{760} \approx 1.21447 \). Rounding to three significant figures, we get \( 1.21\ \text{atm} \) (wait, let's recalculate: \( 923\div760 = 1.21447\), three significant figures is \( 1.21\)? Wait, 923 has three significant figures, 760 is exact (conversion factor), so \( 923\div760 = 1.21447\), so to three significant figures, it's \( 1.21\)? Wait, no, 923 divided by 760: 7601.21 = 919.6, 7601.22 = 927.2. So 923 is between them. Wait, 923/760 = 1.21447, so three significant figures is 1.21 (since the fourth digit is 4, which is less than 5, so we keep the third digit as 1). Wait, no, 1.21447, the first three significant figures are 1, 2, 1 (the fourth is 4). So yes, 1.21 atm? Wait, maybe I made a mistake. Wait, 760 torr is 1 atm. So 923 torr: 923/760 = let's do the division: 760*1 = 760, 923-760=163. 163/760=0.214. So total is 1.214, so three significant figures is 1.21 atm.

Part B:

Step1: Recall conversion factor

We know that \( 1\ \text{atm} = 101325\ \text{Pa} \). So to convert Pa to atm, we use the formula \( P(\text{atm})=\frac{P(\text{Pa})}{101325} \).

Step2: Substitute the value

Given \( P = 4.6\times 10^{4}\ \text{Pa}=46000\ \text{Pa} \), then \( P(\text{atm})=\frac{46000}{101325}\approx 0.4539 \). Rounding to two significant figures, we get \( 0.45\ \text{atm} \) (wait, 4.6 has two significant figures, so the result should have two. 46000/101325 = 0.4539, so two significant figures: 0.45 (since the third digit is 3, less than 5, so we keep the second digit as 5). Wait, 0.4539, two significant figures: the first significant figure is 4, the second is 5 (the third is 3, so we round down). So 0.45 atm.

Answer:

(Part A):
\( \boxed{1.21} \) (Wait, maybe I made a mistake in Part A. Wait, let's check again. 923 torr to atm: 1 atm = 760 torr. So 923 / 760 = 1.21447, so to three significant figures, it's 1.21 atm.