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Any substance that does not conduct electricity when in solution is called a(n) ―
The diagram shows what happens when zinc reacts with hydrochloric acid. Which of these best describes the energy transformation that occurs during this reaction?
Thermal energy - kinetic energy
Kinetic energy -potential energy
Chemical energy - thermal energy
Potential energy - chemical energy
The potential energy diagram of a reaction is shown. Which statement below is correct relating to this reaction?
#1 represents the enthalpy change for this exothermic reaction.
#2 represents the enthalpy change for this endothermic reaction.
#3 represents the enthalpy change for this endothermic reaction.
#4 represents the enthalpy change for this exothermic reaction.
During an exothermic reaction, heat content in the surroundings increases because
heat energy is destroyed during reactions
the reaction absorbs heat energy
the energy contained in the reactants is lower then the products
the energy contained in the products is lower than the reactants
The diagram represents two solids and the temperature of each. What occurs when the two solids are placed in contact with each other?
Heat energy flows from solid A to solid B. Solid A decreases in temperature
Heat energy flows from solid A to solid B. Solid A increases in temperature
Heat energy flows from solid B to solid A. Solid B decreases in temperature.
Heat energy flows from solid B to solid A. Solid B increases in temperature.
The amount of heat energy required to change the temperature of 12 g of gold from 45°C to 15°C is -47 J. What is the specific heat capacity of gold?
The graph represents the uniform heating of a substance, starting with the substance as a solid below its melting point. Which line segment listed below represents an increase in potential energy and no change in average kinetic energy?
Line segment AB
Line segment BC
Line segment CD
Line segment EF
A cast iron skillet is used to fry bacon. For optimal frying, the pan must be heated to about 178 oC from a room temperature of 22.0 oC. It is known that 1.58 x 105 J of heat energy are absorbed by the pan to reach the desired temperature and the specific heat of iron is 0.450 J/g oC. What must the mass of the skillet be?
Experimental Set-up for Calories in a Chocolate Chip Cookie Students designed an experiment to determine the amount of calories in a chocolate chip cookie. A ring stand was used with a clean aluminum soda can hung from the ring that was partially filled with a known mass of water. A thermometer was placed inside the can so that it measured the temperature of the water but did not touch any part of the metal can. Once set-up was complete, an initial water temperature was taken. The cookie was then lit on fire and allowed to completely burn. A final temperature of the water was measured.
Refer to the experimental set-up for calories in a chocolate chip cookie. How does this experiment allow students to measure the calories in a cookie?
The difference in masses before and after the cookie is burned is calculated, then converted into heat energy.
Heat energy from the burning cookie is transferred to the water. The change in water temperature is used to calculate the heat energy from the cookie.
Data from the amount of time for the cookie to burn and the temperature change are used to calculate the heat energy from the cookie.
The cookie is burned until the water reaches a boiling temperature, then masses are compared to calculate the heat energy from the cookie.
When methane, CH4, and oxygen, O2, are mixed in a stove and ignited, a lovely blue flame results. The balanced equation is: CH4(g) + 2O2(g) 2H2O(g) + CO2(g) What can be said about the energy involved in this chemical reaction?
I. The average kinetic energy of the products is greater than that of the reactants.
II. The chemical energy stored in the reactants is greater than the chemical energy stored in the products.
III. Chemical energy in the reactants is changed into heat energy and light energy.
I, II, and III