Midterm Exam Practice

If your teacher directs you to the lab to do an experiment, what is the first thing you should do?

• Start mixing all the chemicals willy nilly.

• Read all the directions to the experiment and make sure you understand them.

• Start playing rock paper scissors with your partner.

• Do the experiment as fast as you can.

Identify the tool in the image

• Test Tube

• Beaker

• Graduated Cylinder

• Balance

What is this tool used to measure?

• Mass (grams)

• Volume (milliliters)

• Length (centimeters)

• Temperature (Celsius)

Round this measurement to 2 sigfigs... 0.00125

• 0.001

• 0.0012

• 0.0013

• 0.12

How many sigfigs are in 304,000,000?

• 1

• 2

• 3

• 9

How many sigfigs are in 120.001200?

• 9

• 3

• 5

• 4

What is 2,300,000 in scientific notation?

• 23 x 10^5

• 2.3 x 10^6

• 2.3 x 10^-6

• 230 x 10^4

Answer explanation

The number before the "x" or multiplication sign should ALWAYS be between 1-10.

So we moved the decimal 6 times to get to 2.3 (which is between 1-10). That is why our exponent is 6.

The exponent is a POSITIVE 6 because positive exponents mean the original number was way bigger than 1. Which it is... 2,300,000 is a number way bigger than 1.

How many meters are in 0.78 km? Hint: use the ladder method and move the decimal.

• 78 m

• 780

• 7.8 x 10^-4 m

• 7.8 x 10^5 m

Answer explanation

Using the ladder method, we would move our decimal 3 times to the right. From the "Kilo" square to the "basic unit" square.

Convert the following temperature to Kelvin... 25 degrees Celsius

Hint: (Kelvin = Celsius + 273)

• 29 K

• 248 K

• 298 K

• 3 K

Answer explanation

25 + 273 = 298

A student performed a lab experiment 5 times and got the following measurements..... 3.45g, 3.40g, 3.48g, 3.45g, 3.50g

Based on this data, describe the results in terms of accuracy/precision. The accepted value is 2.50g

• High precision/High accuracy

• Low precision/high accuracy

• High precision/Low accuracy

• Low precision/low accuracy

Answer explanation

The values are close to each other (precise), but NOT close to the target (accurate).