Enthalpy and Specific Heat

The SI unit of heat and energy is the __________.

• calorie
• heat
• joule
• watt

ΔH value in an endothermic reaction is a positive number.

• True
• False

Which phase of matter has the greatest motion and least orderly arrangement?

• solid
• liquid
• gas

Tags

NGSS.MS-PS3-4

A catalyst works by

• changing the order of the reaction
• increasing the temperature
• lowering the activation energy
• making the activated complex

What type of reaction is shown in the reaction pathway?

• endothermic reaction
• exothermic reaction

Tags

NGSS.HS-PS1-4

N₂ +  3H₂ −->  2NH₃ 
How many moles of ammonium are produced when 3 moles of nitrogen react with hydrogen?

• 6 moles Ammonium
• 1.5 moles ammonium
• 9 moles ammonium
• 9 moles hydrogen

 _?_  is the amount of energy required to raise the temperature of 1 gram of any substance 1^oC.

• Specific heat
• A calorie
• Thermal energy
• Conduction

As 120 g of hot milk cools in a mug, it transfers 20, 000 J of heat to the environment. What is the temperature change of the milk? The specific heat of milk is 2.6 J/g·°C. (Q=mcΔT)

• 64 °C
• 1.56 °C
• 640 °C
• cannot be determined

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-4

If 100 g of aluminum at 145ºC gains 6,800 J of heat, what is the final temperature (T_final) of the aluminum? Aluminum has a specific heat of 0.897 J/gºC. (Q=mcΔT)

• -69°C
• 0.52°C
• 221°C

Tags

NGSS.HS-PS3-1

A  100ml of water is heated by the burning of a biscuit.If he ΔT=20⁰C and the change in mass of the biscuit, Δm =1.35g.Find the enthalpy of the biscuit in kJ/g. (Q=mcΔT)

• 6.19
• 61.9
• 6193
• 8360

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-2

NGSS.HS-PS3-4