SCIENTIFIC MEASUREMENT REVIEW

Question 1

Kelvin

Answer 1

Base unit of temperature reflecting the average kinetic energy of all molecules in a sample (0K absolute zero, 273K freeze, 373K boil)

Question 2

Fahrenheit

Answer 2

-459F Absolute zero, 32F freeze, 212F boil

Question 3

Celsius

Answer 3

-273C absolute zero, 0C freeze, 100C boil

Question 4

Scientific notation

Answer 4

Allows us to write very large and very small numbers easily

Question 5

Converting a positive standard notation to a 10^+ scientific notation

Answer 5

The power is the number of digits after the first digit (eg. 299,700,000 has 8 digits after 2 so it is 2.997x10^8)

Question 6

Converting a negative standard notation to a 10^- scientific notation

Answer 6

The power is the number of 0’s ONLY before an actual number (eg 0.00000542 has 6 zeros so it is 5.42x10^-6)

Question 7

Dimensional analysis

Answer 7

Method for factoring units to find desired one (given unit x desired unit/given unit = desired unit)

Question 8

Systematic errors

Answer 8

Constant errors, decrease in accuracy (measurements are precise but not accurate)

Question 9

Random errors

Answer 9

Due to controlled variables and result in decrease in precision

Question 10

Illegitimate errors

Answer 10

Mistakes from experimenters

Question 11

Accuracy

Answer 11

How close measured value is to the ACTUAL value

Question 12

Precision

Answer 12

How close measured value is to EACH OTHER

Question 13

Absolute error formula

Answer 13

|measured value-true value|

Question 14

Relative error formula

Answer 14

|measured value-true value|/true value

Question 15

Percent error formula

Answer 15

|measured value-true value|/true value x 100%

Question 16

Percent difference formula

Answer 16

Most common measure of accuracy and precision |value 1-value 2|/average of value 1 & 2 x 100%

Question 17

Range

Answer 17

Difference between largest and smallest value (largest value-smallest value)

Question 18

What do smaller values in percent difference and range indicate

Answer 18

Greater precision

Question 19

How is uncertainty in measurements obtained

Answer 19

By estimated the final digit (eg. Burette reading)

Question 20

How is uncertainty in calculations obtained

Answer 20

When adding/subtracting, add the uncertain values. When multiplying/dividing, add the % of uncertain values and change the % to absolute at the end

Question 21

Significant figures

Answer 21

Number of digits in a value that contribute to degree of accuracy of value (Trailing zeros before decimal place are ambiguous and should be avoided using scientific notation)

Question 22

Multiplication & division significant figures

Answer 22

Number of significant figures limited to the measurement with the least number of significant figures (eg. 2.154 x 1.1 = 2.3)

Question 23

Addition & subtraction significant figures

Answer 23

Number of significant figures limited to the measurement with the least amount of decimal places (eg. 1.634 + 0.12 = 1.75)