Atomic Theory & Safety Review

Front

What is percent error?

Back

Percent error is a measure of how inaccurate a measurement is, expressed as a percentage of the true value. It is calculated using the formula: Percent Error = |(Estimated Value - Actual Value)| / Actual Value x 100%.

Front

How do you calculate significant figures in a measurement?

Back

Significant figures are the digits in a number that contribute to its precision. To determine significant figures, count all non-zero digits, any zeros between significant digits, and trailing zeros in a decimal number.

Front

Calculate the percent error if the estimated weight of an object is 8 pounds and the actual weight is 10 pounds.

Back

Percent Error = |(8 - 10)| / 10 x 100% = 20%.

Front

What is the significance of significant figures in calculations?

Back

Significant figures indicate the precision of a measurement. They help ensure that calculations reflect the accuracy of the measurements used.

Front

Calculate 0.020 cm x 50 cm x 11.1 cm and give the answer with the correct number of significant figures.

Back

The answer is 10 cm³, as the calculation must be rounded to two significant figures (from 11.1 cm).

Front

Identify the scientist who discovered the neutron.

Back

James Chadwick discovered the neutron.

Front

What is the formula for calculating percent error?

Back

Percent Error = |(Estimated Value - Actual Value)| / Actual Value x 100%.

Front

How many significant figures are in the number 27000000?

Back

There are 2 significant figures in 27000000, unless specified otherwise (e.g., using scientific notation).

Front

What is the role of neutrons in an atom?

Back

Neutrons are subatomic particles found in the nucleus of an atom and contribute to the atomic mass but do not have an electric charge.

Front

What is the difference between accuracy and precision?

Back

Accuracy refers to how close a measurement is to the true value, while precision refers to how consistent repeated measurements are.