Earth Science Review

The accepted value for the percent by mass of water in a hydrate is 36.0%. In a laboratory activity, a student determined the percent by mass of water in the hydrate to be 37.8%. What is the percent error for the student’s measured value?

• 5.0%

• 4.8%

• 1.8%

• 0.05%

• B is more dense than A.

• A is more dense than C.

• B and C have equal densities

• A and C have equal densities

Tags

NGSS.MS-PS1-2

Under the same conditions of temperature and pressure, three different samples of the same uniform substance will have the same:

• shape

• density

• mass

• volume

• 7.1%

• 2.0%

• 7.7%

• 8.0%

Tags

NGSS.MS-PS1-2

A pebble has a mass of 35 grams and a volume of 14 cubic centimeters. What is its density?

• 0.4 g/cm3

• 2.5 g/cm3

• 490 g/cm3

• 4.0 g/cm3

A student observed a freshly dug hole in the ground and recorded statements about the sediments at the bottom of the hole. Which statement is an inference?

• The hole is 2 meters deep.

• Some of the particles are rounded.

• The sediments were deposited by a stream.

• Over 50% of the sediments are the size of sand grains or smaller.

• 5.5 g

• 15.0 g

• 40.5 g

• 109.3 g

• Density decreases

• Density increases

• Density remains the same

Which statement about a stream is an inference rather than an observation?

• It is clear enough to see the bottom.

• The velocity is 38 cm/sec.

• The water temperature is 15ºC.

• It will dry up next summer.

• 1.00 g/ml

• 1.05 g/ml

• 1.30 g/ml

• 0.95 g/ml