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1. A volumetric flask has a volume of 250 mL and weighs 100 g. If it contains ester, what is the density of the ester?

2. Solve the following equations using the correct number of significant figures:

a. [tex]\( 98.1 \times 0.03 = \)[/tex]

b. [tex]\( 57 \times 7.368 = \)[/tex]

c. [tex]\( \frac{8.578}{4.33821} = \)[/tex]

3. How many significant figures are in each term?

a. [tex]\( 1.40 \times 10^3 = \)[/tex]

b. [tex]\( 6.01 = \)[/tex]

Answer :

Sure! Let's tackle each part of the question step-by-step.

### 1. Density of Ester in the Volumetric Flask

We know:
- The volume of the flask is 250 mL.
- The weight of the ester is 100 grams.

To find the density of the ester, we use the formula:

[tex]\[ \text{Density} = \frac{\text{Mass}}{\text{Volume}} \][/tex]

Substituting in the given values:

[tex]\[ \text{Density of Ester} = \frac{100 \text{ grams}}{250 \text{ mL}} = 0.4 \text{ g/mL} \][/tex]

### 2. Solving Equations with Significant Figures

a. [tex]\( 98.1 \times 0.03 \)[/tex]

- 98.1 has 3 significant figures.
- 0.03 has 1 significant figure.

When multiplying, the result should have the same number of significant figures as the measurement with the fewest significant figures, which is 1 in this case.

The calculated result is approximately [tex]\( 2.943 \)[/tex], but adjusting for significant figures, it should be rounded to [tex]\( 3 \)[/tex].

b. [tex]\( 57 \times 7.368 \)[/tex]

- 57 has 2 significant figures.
- 7.368 has 4 significant figures.

The result should have 2 significant figures, so the answer is rounded to [tex]\( 420 \)[/tex].

c. [tex]\( \frac{8.578}{4.33821} \)[/tex]

- 8.578 has 4 significant figures.
- 4.33821 has 6 significant figures.

The result should have 4 significant figures. The calculated value is approximately [tex]\( 1.977313 \)[/tex], so it should be rounded to [tex]\( 1.977 \)[/tex].

### 3. Significant Figures in Each Term

a. [tex]\( 1.40 \times 10^3 \)[/tex]

The number 1.40 has 3 significant figures.

b. 6.01

The number 6.01 has 3 significant figures.

This solution provides a clear understanding of how to handle density calculations and significant figures in mathematical operations.