How Many Formula Units Are in a Sample of NaCl

question 75

Multiple Choice

How many formula units are in a sample of NaCl that has a mass of 175 g?

• A)2.01 × 10²³ formula units
• B)1.80 × 10²⁴ formula units
• C)6.16 × 10²⁷ formula units
• D)1.05 × 10²⁶ formula units
• E)2.91 × 10^-22 formula units

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Definitions:

Stanines

Derived from the term “standard nines,” this is a standardized score frequently used in schools. Often used with achievement tests, stanines have a mean of 5 and a standard deviation of 2, and range from 1 to 9.

T-scores

Standardized scores with a mean of 50 and a standard deviation of 10, used to compare an individual's score against a normative sample.

Grade Equivalents

A metric used in education to compare a student's test score with the average scores of students in other grades.

NCEs

Normal Curve Equivalents, a type of standardized score used in educational assessments to compare student performance across different age groups and grades.