Heat and Energy Regents Chemistry

Which term refers to the difference between the PE of the products and the PE of the reactants of a chemical change?

• heat of fusion

• heat of reaction

• heat of vaporization

• activation energy

Tags

NGSS.HS-PS3-1

Which statement best describes a chemical reaction in which energy is released?

• It is exothermic and has a negative ΔH

• It is exothermic and has a positive ΔH

• It is endothermic and has a negative ΔH

• It is endothermic and has a positive ΔH

Tags

NGSS.HS-PS1-4

Which statement correctly describes an endothermic chemical reaction?

• The products have higher potential energy than the reactants, and the ΔH is negative.

• The products have lower potential energy than the reactants, and the ΔH is negative.

• The products have higher potential energy than the reactants, and the ΔH is positive.

• The products have lower potential energy than the reactants, and the ΔH is positive.

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-1

Which equation represents an exothermic reaction at 298K? (You need to refer to Table I.)

• 
• 
• 
• 

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-4

Which reaction releases the greatest amount of energy per 2 moles of product? (You need to refer to Table I.)

• 
• 
• 
• 

Tags

NGSS.HS-PS1-4

According to Table I, which salt releases energy as it dissolves? (You need to refer to Table I.)

• KNO₃

• LiBr

• NH₄NO₃

• NaCl

Tags

NGSS.HS-PS1-4

Based on the reaction, what is the approximate ΔH for the formation of 1 mole of H₂O(l)?

• −571.6 kJ

• +571.6 kJ

• −285.8 kJ

• +285.8 kJ

Tags

NGSS.HS-PS1-4

When lithium bromide crystals dissolve in water, the temperature of the water increases. What does this temperature change indicate about the dissolving of lithium bromide?

• It is an endothermic reaction because it absorbs heat.

• It is an endothermic reaction because it releases heat.

• It is an exothermic reaction because it absorbs heat.

• It is an exothermic reaction because it releases heat.

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-4

Given the balanced equation, which statement is true about this reaction?

• It is exothermic and ΔH equals -91.98 kJ.

• It is exothermic and ΔH equals +91.98 kJ.

• It is endothermic and ΔH equals -91.98 kJ.

• It is endothermic and ΔH equals +91.98 kJ.

Tags

NGSS.HS-PS1-4

Which statements describes the forward reaction shown?

• It is endothermic and releases 286 kJ.

• It is endothermic and absorbs 286 kJ.

• It is exothermic and releases 286 kJ.

• It is exothermic and absorbs 286 kJ.

Tags

NGSS.HS-PS1-4