Question

20 formula 1 point
a student fills a graduated cylinder with 9.1 ml of water. the student then places an irregular object in the graduated cylinder. the volume increases to 24.7 ml. the mass of the object is 2.29 g. what is the density of the object? express your answer to 2 decimal places.
answer

21 formula 1 point
what is the density of a metal that weighs 7.67 g and has a volume of 8.6 ml? express your answer with 2 decimal places.
answer

Explanation:

Question 20

Step1: Find the volume of the object

The volume of the object is the difference between the final and initial volume of water. So, \( V = 24.7 - 9.1 = 15.6 \, \text{mL} \) (since \( 1 \, \text{mL} = 1 \, \text{cm}^3 \), volume is also \( 15.6 \, \text{cm}^3 \)).

Step2: Calculate density using \(

ho=\frac{m}{V} \)
Given \( m = 2.29 \, \text{g} \) and \( V = 15.6 \, \text{cm}^3 \), so \(
ho=\frac{2.29}{15.6} \approx 0.15 \, \text{g/cm}^3 \) (rounded to 2 decimal places).

Step1: Recall the density formula \(

ho=\frac{m}{V} \)
Given \( m = 7.67 \, \text{g} \) and \( V = 8.6 \, \text{mL} \) (or \( 8.6 \, \text{cm}^3 \)).

Step2: Substitute values into the formula

\(
ho=\frac{7.67}{8.6} \approx 0.89 \, \text{g/mL} \) (rounded to 2 decimal places).

Answer:

\( 0.15 \, \text{g/mL} \) (or \( 0.15 \, \text{g/cm}^3 \))

Question 21