Question 1

A student measures the mass of a candle and weighing paper at different time intervals while burning the candle. Why is it important to include the mass of the candle drippings in the total mass measurements?

Accepted Answer

To accurately determine the total mass of candle material consumed, including drippings.

Question 2

Given the following data for mass of candle (in grams) at different times: $$t=0$$ min: $$6.89$$, $$t=10$$ min: $$6.59$$, $$t=20$$ min: $$6.29$$, $$t=30$$ min: $$5.99$$, $$t=40$$ min: $$5.69$$, $$t=50$$ min: $$5.39. $$What is the average rate of mass loss per 10 minutes?

Accepted Answer

$$0.30 g/10 $$min

Question 3

If you plot mass of the candle (y-axis) versus time (x-axis), what does the slope of the best-fit line represent in the context of this experiment?

Accepted Answer

The rate at which the candle loses mass over time.

Question 4

Using the equation of a straight line $$y = mx + b$$, where $$y is $$mass and $$x is $$time, what does the $$b$$ value represent in this experiment?

Accepted Answer

The mass of the candle at $$t=0$$ minutes.

Question 5

A student finds the slope of the best-fit line for their mass vs. time graph to be $$-0.03 g/$$min. What does the negative sign indicate?

Accepted Answer

The candle is losing mass over time.

Question 6

If the mass of the candle and weighing paper at $$t=0$$ min is $$7.40 g $$and the mass of the weighing paper alone is $$0.51 g$$, what is the mass of the candle at $$t=0$$ min?

Accepted Answer

$$6.89 g$$

Question 7

After 50 minutes, the mass of the candle is $$5.39 g. If $$the original mass was $$6.89 g$$, what is the total mass lost?

Accepted Answer

$$1.50 g$$

Question 8

Which of the following is the correct equation for the best-fit line if the slope is $$-0.03 g/$$min and the initial mass is $$6.89 g$$?

Accepted Answer

$$y = -0.03x + 6.89$$

Question 9

If a student accidentally forgets to include the mass of the candle drippings in their measurements, how will this affect their calculated rate of mass loss?

Accepted Answer

It will cause the rate to be overestimated.

Question 10

Suppose the mass of the candle decreases linearly over time. If the mass at $$t=20$$ min is $$6.29 g $$and at $$t=40$$ min is $$5.69 g$$, what is the slope of the line (rate of mass loss) in g/min?

Accepted Answer

$$-0.03 g/$$min

Question 11

Why is it important to use a best-fit line rather than connecting the data points directly when analyzing experimental data?

Accepted Answer

A best-fit line averages out random errors and shows the overall trend.

Question 12

If the equation of the best-fit line for mass vs. time is $$y = -0.03x + 6.89$$, what is the predicted mass of the candle after $$25$$ minutes?

Accepted Answer

$$6.14 g$$

Question 13

A student’s graph of mass vs. time shows a curve rather than a straight line. What could this indicate about the burning of the candle?

Accepted Answer

The rate of mass loss changes over time.

Question 14

If the mass of the candle at $$t=0$$ min is $$6.89 g $$and the mass at $$t=50$$ min is $$5.39 g$$, what is the average rate of mass loss per minute?

Accepted Answer

$$-0.03 g/$$min

Question 15

Which of the following best describes the relationship between mass and time in this candle experiment?

Accepted Answer

Mass decreases linearly with time.

Question 16

If a student’s data points do not fit a straight line well, what is the most likely cause?

Accepted Answer

There were experimental errors or inconsistencies in measurement.

Question 17

If the mass of the candle and weighing paper at $$t=30$$ min is $$6.50 g $$and the mass of the weighing paper is $$0.51 g$$, what is the mass of the candle at $$t=30$$ min?

Accepted Answer

$$5.99 g$$

Question 18

Which of the following is a valid reason for using graph paper in this experiment?

Accepted Answer

To visually analyze the relationship between mass and time.

Question 19

If the best-fit line for mass vs. time is $$y = -0.03x + 6.89$$, what is the expected mass of the candle at $$t=60$$ min?

Accepted Answer

$$5.09 g$$

Question 20

Why is it necessary to measure the mass of the weighing paper alone before starting the experiment?

Accepted Answer

To subtract its mass from the total and obtain the mass of the candle only.

Experiment 1: Preparing Graphs – Candle Mass vs. Time

Guida di studio - Domande di pratica

Study guide - Flashcard