Chemistry Sol

The melting point of a substance was determined in four repeated trials to be 56º, 55º, 57.5º, and 55.5ºC. What temperature should be reported as the melting point as a result of these trials?

• 55.0ºC
• 55.5ºC
• 56.0ºC
• 57.5ºC

How should 0.000365 be expressed in proper scientific notation?

• 3.65x10⁴
• 365
• 365x10⁻⁶
• 3.65x10⁻⁴

How many liters are equivalent to 5 milliliters?

• 0.005 L
• 0.05 L
• 500 L
• 5000

Four students each took three temperature readings of a sample of water.  The actual temperature of the sample was 80.0°C.  Which student’s measurements were both accurate and precise?

• Student 1
• Student 2
• Student 3
• Student 4

A compound has a mass of 2.6632 x 10²  g/mol.
The number of significant figures in this mass is --

• 4
• 2
• 5
• 7

A student determined that the density of a sample of tin is 8.00 g/mL, when the actual density of tin is 7.28 g/mL. What was the percent error in the student’s calculation?

• 0.72%
• 9.0%
• 9.9%
• 91%

A student was instructed to carry out an experiment that illustrates the law of conservation of mass. The teacher indicated that the experiment should be carried out three times. The student plans to report the average of the three results. What can the student do to maximize the reliability of the data collected?

• Report the result that came closest to the class average.

• Conduct each trial using the same balance.

• Report the average of the two most similar values only.

• Perform each of the trials on different days

Tags

NGSS.MS-PS1-5

To determine if a reaction is exothermic, a student should use a -

• pH probe
• motion sensor
• pressure sensor
• temperature probe

Tags

NGSS.HS-PS1-4

NGSS.HS-PS1-5

Which is the best use for a fume hood

• storing glassware
• removing toxic vapors
• covering volatile compounds
• mixing chemicals that release O₂

Tags

NGSS.HS-ETS1-3

Which of the following describes this separation technique

• chromatography
• filtration
• crystallization
• distillation