Trimester 2 Midterm 2024-2025

Who is your teacher?

• Andersen
• Phillips
• Valencia

What period is this?

• 1
• 2
• 3
• 4
• 5

First Name

Evaluate responses using AI:

OFF

Last Name

Evaluate responses using AI:

OFF

1. The two models have a different number of ________ atoms.

• hydrogen
• oxygen
• carbon

2. Formic acid is represented by ____________

• Model 1
• Model 2

3. Students are studying a compound that is a white crystalline powder at room temperature. The students build a ball-and-stick model of this powder. Which model demonstrates the structure of the compound?

• A
• B
• C
• D

4. A student is given a hydrochloric acid (HCl) solution in a test tube and a small piece of magnesium (Mg) for an experiment. The student makes these observations about their properties: The HCl solution is clear and colorless Mg is a gray metal and it is not soluble in water The student adds the piece of Mg to the HCl solution and records these observations. Which two observations best show that a chemical reaction occurs?

• The piece of Mg initially sinks to the bottom
• The solution remains colorless throughout the process
• The piece of Mg slowly disappears and a gas bubbles out of the solution
• A popping sound is heard when the teacher holds a lighted match over the solution

5. Students are asked to design a cold pack. They mix different amount of ammonium chloride (NH4Cl) with 100 milliter (mL) samples of water at 30 degrees Celsius (°C) in small, sealable plastic bags. The results are shown in the table below. Based on the data, approximately how much NH4Cl should be mixed with water to make a cold pack with the lowest temperature without using more NH4Cl than needed?

• between 20 and 30 g
• between 30 and 40 g
• between 40 and 50 g
• between 50 and 60 g

6. A student made a model of a chemical reaction in which the mass is conserved. Oxygen (O) atoms are shown in white and hydrogen (H) atoms are shown in gray. Which words correctly complete the sentence below? This model is ___________ because the number of atoms shown in the reactants and the products are__________.

• correct, the same
• Incorrect, the same
• correct, different
• incorrect, different