Basic Laboratory Activities

Which procedure represents the safest technique to use for diluting a concentrated acid?

• 1. Add the acid to the water quickly.

• 1. Add the water to the acid quickly.

• 1. Add the acid slowly to the water with steady stirring.

• 1. Add the water slowly to the acid with a steady stirring.

Which procedure is the safest to follow when using an open flame to heat the contents of a test tube that contains a flammable mixture?

• 1. Cork the test tube and then heat it gently near the bottom only.

• 1. Heat the open test tube gently near the bottom only.

• 1. Cork the test tube and place it in a beaker of water, then heat the water in the beaker.

• Place the open test tube in a beaker of water, then heat the water in the beaker.

3. A student has to measure the diameter of a test tube (as shown in the diagram below) in order to calculate the tube's volume. Based on the diagram, the tube's diameter is closest to

• 1.25 cm

• 2.32 cm

• 3.25 cm

• 12.5 cm

The diagram below represents a portion of a burette.

What is the reading of the meniscus?

• 39.2 mL

• 39.5 mL

• 40.7 mL

• 40.9 mL

In order to read the volume of the liquid most accurately, the eye of the student should be

• Level with the meniscus

• above the meniscus

• at the bottom of the cylinder

• at the top of the cylinder

As a result of dissolving salt in water, a student found that the temperature of the water increased. From this observation alone, the student should conclude that the dissolving of the salt

• produced an acid solution

• produced a basic solution

• was endothermic

• was exothermic

The volume of an acid required to neutralize exactly 15.00 milliliters of a base could be measured most precisely if it were added to the base solution from a

• 100-mL graduate

• 125-mL Erlenmeyer flask

• 50-mL burette

• 50-mL beaker

Which diagram represents a graduated cylinder?

• 
• 
• 
• 

Refer to the experimental data below.

Mass of empty graduated cylinder

= 141 g

Mass of graduated cylinder and distilled water = 163 g

Volume of distilled water

= 25.3 mL

Based on the experimental data collected, what is the density of the distilled water?

• 1.0 g/mL

• 0.253 g/mL

• 0.87 g/mL

• 1.15 g/mL

Which diagram below represents a pipette?

• 
• 
• 
•