Thermochemistry

Calculate the amount of heat liberated from 366g of mercury when it cools from 77.0^oC to 12.0^oC. Specific heat of Hg = 0.140kJ/g*^oC

Answer explanation

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NGSS.HS-PS3-4

NGSS.HS-PS3-1

A 12.1g piece of aluminum at 81.7^oC is placed in a calorimeter containing water at 23.4^oC. If the final temperature of the system is 24.9^oC, what is the mass of the water? specific heat of Al = 0.900 J/g*^oC; specific heat of water = 4.184 J/g*^oC

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NGSS.HS-PS3-4

NGSS.HS-PS3-1

Calculate the standard enthalpy change for the reaction :

2Al_(s)+Fe₂O_3(s) --> 2Fe_(s) + Al₂O_3(s)

given that:

2Al_(s)+3/2O_2(g) --> Al₂O_3(s) ΔH^o_rxn=-1669.8kJ/mol

2Fe_(s)+3/2O_2(g) --> Fe₂O_3(s) ΔH^o_rxn=-822.2kJ/mol

Answer explanation

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NGSS.HS-PS1-4

Calculate the enthalpy change for the reaction:

2C_(graphite)+3H_2(g)--> C₂H_6(g)

given that:

C_(graphite)+O_2(g) --> CO_2(g) ΔH^o_rxn= -393.5kJ/mol

H_2(g)+1/2O_2(g) --> H₂O_(l) ΔH^o_rxn= -285.8kJ/mol

2C₂H_6(g)+7O_2(g) --> 4CO_2(g)+6H₂O_(l) ΔH^o_rxn= -3119.6kJ/mol

Answer explanation

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NGSS.HS-PS1-4

Given the following data:

H_2(g) --> 2H_(g) ΔH^o_rxn= 436.4kJ/mol

Br_2(g) --> 2Br_(g) ΔH^o_rxn= 192.5kJ/mol

H_2(g) + Br_2(g) --> 2HBr_(g) ΔH^o_rxn= -72.4kJ/mol

Calculate ΔH^o_{rxn for}

H_(g) + Br_(g) --> HBr_(g)

Answer explanation

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Tags

NGSS.HS-PS1-4

Heat flows from _______ to ______ objects

• cooler to warmer
• warmer to warmer
• warmer to cooler
• cooler to cooler

Tags

NGSS.HS-PS3-4

The transfer of thermal energy between objects of different temperatures is called...

• temperature
• heat
• internal energy
• none of these

Tags

NGSS.HS-PS3-4

When thermal energy is added to a substance, the substance's particles move:

• More rapidly at an increased distance from each other.

• More rapidly with less distance between each other.

• More slowly with a greater distance between each other.

• More slowly with a reduced distance between each other.

Tags

NGSS.HS-PS3-4

NGSS.HS-PS3-2

Heat transfer by conduction occurs when...

• particles bump into each other
• large numbers of atoms move from place to place
• atoms give off heat in the form of electromagnetic waves
• electromagnetic waves travel from place to place through a vacuum

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NGSS.HS-PS3-4

Heat transfer by convection occurs when...

• electrons bump into other electrons
• large numbers of atoms move from place to place
• atoms give off heat in the form of electromagnetic waves
• electromagnetic waves travel from place to place through a vacuum

Tags

NGSS.HS-PS3-4

NGSS.HS-ESS2-3