Properties of Matter and Measurement Flashcards

Comprehensive practice questions covering matter properties, branches of chemistry, measurement units, accuracy, precision, and experimental error analysis based on lecture notes.

What is Chemistry defined as in the study of matter?

Chemistry is the study of matter and the changes it undergoes, including its composition, structure, properties, and the energy changes involved in these processes.

What are the characteristics of a Physical Property?

These are characteristics that can be observed and measured without changing the identity and composition of the substance.

What is the difference between Intensive and Extensive Properties?

Intensive Properties do not depend on the amount of matter (inherent properties), whereas Extensive Properties depend on the amount of matter and change when the amount of substance changes.

What does a Chemical Property refer to?

It refers to the ability of a substance to change or transform into different substances.

Match the branches of Chemistry to their focus: Organic, Inorganic, Biochemistry, Analytical, and Physical.

Organic: carbon; Inorganic: metals, minerals, construction; Biochemistry: living things; Analytical: laboratory/quantitative research; Physical: the "why" and "how" of chemical systems.

What is the SI unit and instrument used for measuring Temperature?

The instrument is a thermometer and the unit is Kelvin ($K$).

What is the SI unit and instrument used for measuring Mass?

The instrument is a balance and the unit is kilogram ($kg$).

What is the definition of Accuracy?

Accuracy refers to how close a measured value (or the average of repeated measurements) is to the accepted (true) value.

What is the formula for the Mean ($\bar{x}$) of a data set?

$\bar{x} = \frac{\sum x}{n}$, where $\sum x$ is the sum of all measurements and $n$ is the number of measurements.

What is Precision and how is it measured?

Precision refers to how close repeated measurements are to each other (consistency). It is measured by Standard Deviation (SD).

How does Standard Deviation (SD) relate to precision?

A low SD indicates high precision (data points are clustered together), while a high SD indicates low precision (data points are scattered).

What is the formula for Standard Deviation (SD)?

$$SD = \sqrt{\frac{\sum(x - \bar{x})^2}{n - 1}}$$

What is Uncertainty in measurement?

It refers to the range of doubt in a measurement, occurring because no measurement is perfectly exact due to instrument limits; it is often expressed as standard deviation.

What is the formula for Experimental Error?

$$\text{Error} = | \text{accepted value} - \text{experimental value} |$$

What is the formula for Percent Error?

$$\text{Percent Error} = \frac{| \text{measured value} - \text{actual value} |}{\text{actual value}} \times 100$$

What are the characteristics of Systematic Error?

They are consistent, repeatable errors that occur in the same direction, introduce bias, affect accuracy, and cannot be reduced by increasing the number of measurements.

What are the characteristics of Random Error?

They are unpredictable, variable fluctuations caused by uncontrollable factors; they affect precision and their impact can be reduced by increasing the number of measurements and averaging them.

What are the four general sources of Experimental Error?

1. Instrumental Error, 2. Environmental Error, 3. Human Error, 4. Procedural Error.

How can experimental error be minimized?

Through careful experimental design, proper instrument calibration, using appropriate equipment, following standardized procedures, taking multiple measurements, using controls, and worker training.