Endo vs. Exo

In a chemical reaction, which of the following occurs?

• Absorbing heat during breaking bonds of reactants

• Releasing heat during forming of new bonds of products

• Both absorbing and releasing of heat occurs during a reaction

• sometimes ONLY absorbing of heat occurs or sometimes ONLY releasing of heat occurs

A lizard egg needs a temperature of 26-30 ° C to hatch properly. You place it next to a pouch of water which is 22 °C. What type of chemical do you need to add to the water to help warm the egg?

• Baking soda and vinegar because it will be endothermic reaction that heats the egg

• Calcium chloride because it will be exothermic reaction that warms the egg.

• Only water will help warm the egg.

In an exothermic reaction, heat is ...

• taken in or absorbed
• given out or released

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-4

In an endothermic reaction, heat is ...

• taken in or absorbed
• given out or released 

Tags

NGSS.HS-PS1-4

What type of reaction occurs in a hand warmer

• exothermic
• endothermic

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-4

Baking bread and cooking an egg are examples of....?

• Endothermic processes
• Exothermic processess
• None of these 

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

NGSS.MS-PS3-5

If a chemical reaction is EXOTHERMIC, the temperature of the environment will....

• Stay the same

• Increase

• Decrease

A student mixed two chemicals to allow them to react. The temperature before the reaction was 25 ° C. The temperature after the reaction was 18° C. Which of the following is true?

• The temperature increased

• It is an endothermic reaction

• It is an exothermic reaction

• Too hard to answer

A student mixed two chemicals to allow them to react. The temperature before the reaction was 25 ° C. The temperature after the reaction was 18° C. Which of the following is true?

• The ΔH will be positive because its endothermic.

• The ΔH will be negative because its endothermic.

• The ΔH will be positive because its exothermic.

• The ΔH will be negative because its exothermic.

When iron nails get rusty, heat is released.  What process is this?

• Exothermic
• Endothermic