Physics Class 10 Practical 18 Important Viva Questions with Answers (density of liquid using syringe )

 PRACTICAL 18

To find the density of a liquid using 5 ml syringe (instead of density bottle).

VIVA VOCE

Q1: What is the aim of the experiment?

A1: The aim of the experiment is to find the density of a liquid using a 5 ml syringe instead of a density bottle.

Q2: What is the basic principle used to determine the density of a liquid in this experiment?

A2: The basic principle involves measuring the mass of a known volume of the liquid and then calculating its density using the formula \( \rho = \frac{m}{V} \), where \( \rho \) is density, \( m \) is mass, and \( V \) is volume.

Q3: Describe the procedure of the experiment briefly.

A3: The procedure involves the following steps:

1. Weigh an empty 5 ml syringe.

2. Fill the syringe with the liquid up to the 5 ml mark.

3. Weigh the syringe filled with the liquid.

4. Calculate the mass of the liquid by subtracting the mass of the empty syringe from the mass of the filled syringe.

5. Calculate the density using the mass and the known volume (5 ml) of the liquid.

Q4: How do you ensure the syringe is accurately filled to 5 ml?

A4: Ensure the syringe is accurately filled to 5 ml by drawing the liquid up to the 5 ml mark on the syringe scale, making sure there are no air bubbles, and checking the meniscus at eye level.

Q5: Why is it important to ensure no air bubbles are present in the syringe?

A5: Air bubbles can lead to inaccurate volume measurement, which in turn affects the calculation of density.

Q6: What formula is used to calculate the density of the liquid?

A6: The density (\( \rho \)) of the liquid is calculated using the formula \( \rho = \frac{m}{V} \), where \( m \) is the mass of the liquid and \( V \) is the volume (5 ml).

Q7: How do you calculate the mass of the liquid in the syringe?

A7: The mass of the liquid is calculated by subtracting the mass of the empty syringe from the mass of the syringe filled with the liquid.

Q8: What units are used for measuring mass and volume in this experiment?

A8: Mass is measured in grams (g) and volume is measured in milliliters (ml).

Q9: How do you ensure accuracy in your mass measurements?

A9: Accuracy can be ensured by using a precise balance, ensuring the syringe is clean and dry before weighing, and taking multiple readings to average the results.

Q10: What are the potential sources of error in this experiment?

A10: Potential sources of error include inaccurate filling of the syringe, presence of air bubbles, evaporation of the liquid, and inaccuracies in the balance used for weighing.

Q11: How can you minimize these errors?

A11: Minimize errors by carefully filling the syringe, ensuring no air bubbles, quickly measuring the mass to prevent evaporation, and using a calibrated, high-precision balance.

Q12: Why might you use a syringe instead of a density bottle in this experiment?

A12: A syringe can be used instead of a density bottle for convenience, to measure small volumes accurately, and because it allows for easy handling and precise control over the volume of liquid measured.

Q13: What do you do if the liquid you are measuring is volatile?

A13: If the liquid is volatile, minimize exposure to air by quickly transferring it to the syringe, capping the syringe if possible, and performing the measurements promptly to reduce evaporation.

Q14: What is the significance of knowing the density of a liquid?

A14: Knowing the density of a liquid is important for identifying the liquid, determining its concentration, and in various applications such as quality control, formulation, and scientific research.