1 Accuracy refers to how close a measurement is to: A Other measurements B The true value C Zero D Maximum value
3 Uma is conducting an experiment to find the empirical formula of a compound. She collects data on the masses of elements. What is empirical formula based on? A Molecular mass B The simplest whole-number ratio of atoms C The actual number of atoms D The structural arrangement
4 Chloe is preparing a lab report. She includes a section on data analysis where she interprets the results. What is the purpose of data analysis in a lab report? A To list all equipment used B To explain the meaning of the data and relate it to the hypothesis C To describe the procedure D To include safety precautions
5 Emma is conducting an experiment to determine the density of a metal. She measures the mass and volume. What is the formula for density? A Density = mass × volume B Density = mass / volume C Density = volume / mass D Density = mass + volume
6 The variable that responds to changes is called: A Independent variable B Controlled variable C Dependent variable D Fixed variable
7 The vertical axis of a graph usually represents: A Independent variable B Constant C Dependent variable D Title
9 Ahmed is collecting data on the pH of different solutions. He uses a pH meter to measure the pH. What type of data is pH measurement? A Qualitative data B Quantitative continuous data C Quantitative discrete data D Ordinal data
10 Quantitative data is data that: A Is descriptive B Is numerical C Is based on opinions D Has no units
11 Bar graphs are mainly used to compare: A Continuous data B Time-based data C Different categories D Trends
13 Oliver is conducting an experiment to determine the enthalpy change of a reaction. He measures the temperature change. What is the unit of enthalpy change? A Joules B Kelvin C Celsius D Grams
14 David is analyzing data from an experiment on the rate of reaction. He calculates the average rate from multiple trials. Why is it important to repeat experiments and collect multiple data points? A To increase the accuracy and reliability of the results B To make the experiment more time-consuming C To confuse the results D To avoid using a control
15 Patricia is collecting data on the mass of a precipitate. She uses a filter paper to collect the precipitate. What is a potential source of error in this measurement? A Evaporation of the solution B Loss of precipitate during filtration C Incorrect pH D Temperature fluctuations
16 Lara is conducting an experiment and wants to ensure that her results are reliable. She repeats the experiment multiple times. What is the purpose of repetition in experimental data collection? A To increase the chance of getting the desired result B To reduce random errors and improve precision C To make the experiment longer D To eliminate the need for a control
17 Precision refers to: A Closeness to true value B Exactness of equipment C Repeatability of measurements D Accuracy only
18 Which best represents good experimental design? A Many changing variables B One variable changed at a time C No controls D Guessing results
20 Analyzing data means: A Ignoring results B Organizing and interpreting results C Repeating experiment D Changing hypothesis
21 Which type of graph is best for showing proportions? A Line graph B Bar graph C Pie chart D Scatter plot
22 Khalid is analyzing data and finds that the mean is 5.2 and the median is 5.0. What does this suggest about the data? A The data is perfectly symmetrical B The data is slightly skewed C The data has no outliers D The data is invalid
23 Tina is calculating the percentage error in her experiment. She uses the formula: (|experimental value - theoretical value| / theoretical value) × 100. What does a small percentage error indicate? A The experiment was precise but not accurate B The experiment was accurate C The experiment had significant errors D The experiment was not repeatable
24 Quinn is measuring the volume of a liquid using a graduated cylinder. He reads the meniscus incorrectly each time. What type of error is this? A Systematic error B Random error C Instrumental error D Parallax error
25 Zara is conducting an experiment on the rate of reaction. She measures the time it takes for a reaction to complete. What is the unit of measurement for time in the SI system? A Second B Minute C Hour D Millisecond