chapter 6 smartbook chemistry

A 3.56-g piece of copper metal is heated from 20.5°C to 325°C. Calculate the heat absorbed (in kJ) by the metal if the specific heat of copper is 0.385 J/g⋅K. (Don't forget that ΔT will be the same numeric value either in K or °C units, since their degree size is equal. This would not be true for °F whose degree increment is smaller.)

+0.417 kJ

Which of the following statements correctly describe exothermic and endothermic reactions? Select all that apply

- The reactants in an endothermic reaction are lower in energy than the products - An exothermic reaction is one that releases heat to its surroundings - If the container of a reaction becomes colder during the reaction, the reaction is endothermic

84 g of a metal at an initial temperature of 72°C releases 553 J of heat. Calculate the final temperature of the metal if its specific heat capacity is 0.13 J/g⋅K.

21 C

Match the effects of the following combinations of Reactions 1 and 2 with the reaction resulting from these combinations. Reaction 1: A → 2C Reaction 2: C → B Rxn 1 + (-Rxn 2) Rxn 1 + 2(Rxn 2) (-Rxn 1) + (-Rxn 2)

A + B → 3C A → 2B B + C → A (corresponds with order in the question)

Select all that apply The internal energy change for a reaction is related to enthalpy by equation ΔE = ΔH - PΔV. This equation tells us that ΔH is very close to ΔE if there is no volume change in the reaction. In which of the following situations would ΔH give a good approximation of ΔE? Select all that apply.

A reaction in which the change in the number of moles of gas present is zero A reaction involving only solids and liquids

Which of the following symbols is used to indicate internal energy?

E

True or false: If an ice cube is placed on a hot stove, heat transfers from the ice cube to the stove.

False

Match each set of conditions with the type of compound when that compound is under standard conditions at a given temperature.

Gas: 1 atm Aqueous Solution: 1 M Pure Substance: Stable form at the given temperature and 1 atm of pressure

Use the equation for specific heat capacity to determine the function needed to solve for the variables associated with temperature change.

Heat - c × mass x ΔT Mass of substance - q/c×ΔT Change in temperature - q/mass×c Specific heat capacity - q/mass×ΔT

An experiment is developed to determine the energy change during a precipitation reaction, represented by the following balanced equation: AgCH3COO (aq) + NaCl (aq) → NaCH3COO (aq) + AgCl (s) Which of the following are part of the system? Select all that apply.

NaCl Reason: Correct. NaCl is a reactant and is part of the chemical system being studied. AgCH3COO Reason: Correct. AgCH3COO is a reactant and is part of the chemical system being studied.

Generate the equation A + 2B → 2D from a combination of the reactions provided. Reaction 1: A + 2B → 2C Reaction 2: C → D How must reactions 1 and 2 be combined to sum to the overall reaction?

Reaction 1 + 2(Reaction 2) Reason: Yes, by doubling reaction 2, C will cancel.

Which of the following experimental values are used to solve for the specific heat capacity of a substance? Select all that apply.

The heat absorbed or released (q) The temperature change The mass of the substance

Select all that apply Hot coffee is poured into a mug. It slowly cools, releasing heat to the environment. If we consider the coffee to be the system, which of the following are part of the surroundings? Select all that apply.

The table underneath the mug The mug The air in the room

Which of the following statements correctly describe the relationship between the volume of a chemical system and work? Select all that apply.

The work done by an expanding gas is calculated using the equation w = -PΔV. The work done by an expanding gas is calculated using the equation w = -PdeltaV The expansion of a gas can provide mechanical work.

The study of heat changes in chemical reactions is called

Thermochemistry

The study of energy and its transformations is called ______.

Thermodynamics

True or false: Both heat and work can be measured in joules.

True ALL ENERGY CAN BE MEASURED IN JOULES

The specific heat capacity, abbreviated with the letter ______, is the quantity of _____required to change the temperature of ______gram of an object by 1 _____ .

c, heat, 1, Kelvin

A thermochemical equation links a reaction's stoichiometry to its ________ change or ΔHrxn.

enthalpy

In a thermochemical equation, the _____ change is always written next to the balanced chemical equation.

enthalpy

Based on the first law of thermodynamics, the energy gained by a system is _____ the energy lost by the surroundings.

equal to

The sum of all the potential and kinetic energies for all particles in a system is called the total _________ energy (E) of the system.

internal energy

Work may be done in a chemical system by a change in volume as a gaseous component expands or contracts at constant_______

pressure

A constant _____ calorimeter is most frequently used to measure ΔH for a reaction in aqueous solution, whereas a constant _____ calorimeter is usually used to measure the heat of a combustion reaction.

pressure, volume

The symbol _____ always indicates heat (or thermal energy), which is transferred as a result of a difference in temperature between a system and its surroundings.

q

Thermodynamic parameters are usually calculated for compounds under _________conditions, since values tend to vary somewhat with conditions. To be in this state, a gas must have a pressure of 1 ______, and a solution must have a concentration of 1 ______

standard, atm, M

Which of the following statements correctly describe specific heat capacity (c)? Select all that apply. Multiple select question. The specific heat for a substance has the same value regardless of the size of the sample. A substance with a low specific heat requires more heat to raise its temperature than a substance with high specific heat, assuming equal masses. The units of specific heat are J/g⋅K. The symbol for specific heat is c. The units of specific heat are J/mol⋅K.

the specific heat for a substance has the same value regardless of the size of the sample. The units of specific heat are J/g⋅K. The symbol for specific heat is c.

Energy transferred when an object is moved by a force results in ______ being done on that object.

work

Match each type of energy change with its associated symbol.

work=w heat=q internal energy=E

Which of the following relationships are true? Select all that apply.

ΔH = q (at constant P) ΔE = q + w (under any conditions)

Which of the following relationships are true? Select all that apply. ΔH = q (at constant P) ΔE = q + w (under any conditions) ΔE = ΔH + w (at constant P) ΔH = q + w (at constant P)

ΔH = q (at constant P) ΔE = q + w (under any conditions) ΔE = ΔH + w (at constant P)

Match each type of calorimeter with the thermochemical property that it measures.

ΔH- Constant pressure (coffee cup) calorimeter correct Toggle Button Unavailable. ΔE- Bomb (constant volume) calorimeter