1.
An outlier in data is:
A
Average value
B
A value far from others
C
Correct value
D
Repeated value
2.
Oliver is studying the rate of a chemical reaction by measuring the change in concentration over time. He plots a graph of concentration vs. time. What can he determine from the slope of the graph?
A
The equilibrium constant
B
The rate of reaction
C
The activation energy
D
The enthalpy change
3.
Which type of data is temperature?
A
Qualitative
B
Quantitative
C
Descriptive
D
Categorical
4.
Which variable is deliberately changed in an experiment?
A
Dependent variable
B
Controlled variable
C
Independent variable
D
Constant
5.
Which improves accuracy of an experiment?
A
Faulty instruments
B
Careful measurement
C
Guessing values
D
Ignoring errors
6.
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
7.
Which term describes closeness of repeated readings?
A
Accuracy
B
Error
C
Precision
D
Validity
8.
Xia is analyzing data from an experiment and finds a correlation between two variables. What does a correlation indicate?
A
That one variable causes the other
B
A relationship between two variables
C
That there is no relationship between the variables
D
That the data is invalid
9.
Calibration of instruments improves:
A
Precision only
B
Accuracy
C
Graphing
D
Hypothesis
10.
Nora is analyzing data from a reaction. She calculates the rate of reaction from the slope of a concentration vs. time graph. What does a steeper slope indicate?
A
A slower reaction rate
B
A faster reaction rate
C
The reaction has stopped
D
No change in reaction rate
11.
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
12.
Which tool is commonly used to collect experimental data?
A
Dictionary
B
Balance
C
Notebook
D
Calculator
13.
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
14.
Which term describes correctness of result?
A
Precision
B
Accuracy
C
Trend
D
Range
15.
A valid conclusion must be:
A
Based on feelings
B
Based on experimental evidence
C
Based on guess
D
Based on others’ work only
16.
Which is a source of experimental error?
A
Careful work
B
Faulty apparatus
C
Controlled variables
D
Accurate tools
17.
Julia is calculating the average of her experimental data. She adds all the values and divides by the number of values. What is this measure of central tendency called?
A
Median
B
Mode
C
Mean
D
Range
18.
The vertical axis of a graph usually represents:
A
Independent variable
B
Constant
C
Dependent variable
D
Title
19.
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
20.
Khalid is comparing two sets of data from an experiment. He wants to know the spread of the data. Which statistical measure should he use?
A
Mean
B
Median
C
Mode
D
Range
21.
Fatima is analyzing her data and calculates the mode. What does the mode represent?
A
The average of the data
B
The middle value of the data
C
The most frequently occurring value
D
The range of the data
22.
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
23.
Ibrahim is analyzing data from an experiment. He notices a trend that as temperature increases, solubility increases. What type of relationship is this?
A
Direct relationship
B
Inverse relationship
C
No relationship
D
Exponential relationship
24.
Nora is recording the pH of a solution over time. She notices that the pH values are fluctuating. What should she do to improve the accuracy of her data?
A
Ignore the fluctuations
B
Take more readings and average them
C
Stop the experiment
D
Change the pH meter
25.
The first step in a scientific investigation is:
A
Conclusion
B
Experiment
C
Observation
D
Data analysis
26.
Victor is analyzing data from a reaction. He notices that the data points on his graph form a straight line. What does a straight line graph indicate about the relationship between variables?
A
It is a direct proportional relationship
B
It is an inverse relationship
C
There is no relationship
D
It is a quadratic relationship
27.
Which type of graph is best for showing proportions?
A
Line graph
B
Bar graph
C
Pie chart
D
Scatter plot
28.
Emma is recording the temperature of a solution at regular intervals. She creates a table to organize her data. What is the first step in data analysis after collection?
A
Drawing conclusions
B
Organizing and presenting the data in tables or graphs
C
Discarding data that does not fit
D
Changing the hypothesis
29.
Which improves credibility of results?
A
Single trial
B
Repeated experiments
C
Ignoring errors
D
Changing hypothesis
30.
Random errors mainly affect:
A
Accuracy
B
Precision
C
Both equally
D
Neither