Feel the Heat Gizmos Answer Key with complete solution 2021 Guaranteed A+ Score: Updated

Feel the Heat Gizmos Answer Key with complete solution 2021 Guaranteed A+ Score: Updated

by putting ice packs filled with water into the freezer, the water becomes into ice. The hand

warmers have items inside that with friction create heat.

The cold comes from the ice and chemicals, the hot comes from the friction that we give to

the warmers that cause heat inside.

Name:

Student Exploration: Feel the Heat

Directions: Follow the instructions to go through the simulation. Respond to the questions and

prompts in the orange boxes.

Vocabulary: calorimeter, conductor, controlled experiment, dissolve, endothermic, exothermic, insulator,

solute, solution, solvent, surroundings, system

Prior Knowledge Questions (Do these BEFORE using the Gizmo.)

Eduardo hurts his knee during a basketball game. The trainer applies a cold pack, which gets cold after being

squeezed. The next day, Eduardo’s friend Beth is going sledding. Beth buys some hand warmers and puts

them into her gloves. All morning, her hands stay toasty warm.

1. How do you think these devices work?

2. Where do you think the “cold” and the heat comes from?

Gizmo Warm-up

As you saw with the instant cold pack and the hand warmers, some reactions absorb

energy while others release it. In the Feel the Heat Gizmo, you will explore these energy

changes while making your own hot and cold packs.

To begin, select the TEST POWDERS tab. Drag a bottle of NaC2H3O2 (sodium acetate)

from the shelf. Using the sliders, decide how much water and powder to add. Note the

beginning temperature, and then press Play ( ) to see what happens.

1. Did the temperature go up or down?

2. Experiment with different powders until you find one that produces the opposite effect.

What powder did you use?

When a powder dissolves in water a solution is formed. The powder is the solute and the water is the

solvent. Oftentimes energy changes accompany the formation of a solution. When added to water, some

Up

Ammonium Nitrate

Date: 03/01/2021

Orange

They break apart

They attach to the NaC2H2O2 bonds

light blue

It goes inward

It goes outwards

powders cause the resulting solution to get hot, while others make it cold. Some powders don’t produce a

temperature change at all. When energy changes do occur, they can be put to good use.

Activity A:

Molecular view

Get the Gizmo ready:

● Click Reset ( ).

● Drag a bottle of NaC2H3O2 from the shelf.

Introduction: The reactions in this activity are performed within a calorimeter, an insulated device that keeps

heat from escaping, enabling you to accurately record temperature changes.

Question: Why does the temperature change when a powder is dissolved in water?

1. Observe: Turn on Show molecular view, and notice the water molecules. Set the Water volume to 100

mL and the Powder mass to 20 g, and then click Play. Click Pause ( ) after adding the powder. You

should now see some sodium acetate in the water.

A. What color represents the bonds between the particles of NaC2H3O2?

B. Click Play. Watch the animation a few times. What happens to the NaC2H3O2 bonds?

C. What happens to the bonds between water molecules?

D. What color are the new bonds that form between the solute and solvent?

2. Investigate: In the animation, the purple arrows represent energy that is being absorbed from the water,

while the orange arrows show energy that is being released into the solution.

A. Replay the animation, carefully noting the purple arrows. What does this absorbed energy do?

B. Now replay the animation but focus on the orange arrows. What occurs every time an orange arrow

is released?

Powered by TCPDF (www.tcpdf.org)