8th Grade Science Semester Exam Review

Josey is conducting a lab investigating the effects of acid rain. While reading the lab instructions, she notices the safety symbol shown above. What is the meaning of this safety symbol?

• Wear safety gloves while performing this experiment.

• Caution: Chemicals in this lab are corrosive.

• Wash your hands after handling the chemicals in this lab.

• Caution: Chemicals in the experiment will be very hot.

A student drops a beaker on the floor, breaking it. Which of the following should the student do FIRST?

• Tell the teacher about the accident.

• Find a new beaker to use.

• Look for a broom and dustpan.

• Have your lab partner clean it up for you.

Scientists perform many trials for each experiment because —

• they want to improve their public image

• they want to improve the reliability of the results

• they have to rewrite the hypothesis

• they have to decide how to publish the data

Tags

NGSS.MS-LS1-5

Which is the volume of the object in the beaker shown above?

• 125 mL

• 150 mL

• 275 mL

• 470 mL

What is the temperature shown on the thermometer?

• -28 ° C

• -12 ° C

• -26 ° C

• -15 ° C

Structures A and B are located in the

• valence shell

• energy levels

• electron cloud

• nucleus

Tags

NGSS.MS-PS1-1

Which Bohr model represents Boron?

• 
• 
• 
• 

Tags

NGSS.MS-PS1-1

This is the periodic entry for the element Boron. What is the atomic mass of Boron?

• 5

• 10.81

• 13

• 15.81

Which of these parts of an atom has a negative charge?

• electron

• proton

• neutron

• nucleus

Which part of the atom has a positive charge?

• electron

• proton

• neutron

• nucleus