CHM143-CHAPTER 1 (PART 1)

Front

What is an isolated system?

Back

An isolated system is one where neither energy nor matter can be exchanged with the surroundings.

Front

What is an endothermic reaction?

Back

An endothermic reaction is a chemical reaction that absorbs heat from its surroundings, resulting in a temperature decrease in the surroundings.

Front

What is the standard enthalpy of formation (ΔHf°)?

Back

The standard enthalpy of formation (ΔHf°) is the change in enthalpy when one mole of a compound is formed from its elements in their standard states.

Front

Which molecule has a ΔHf° value of zero?

Back

Elements in their standard state, such as Cl2(g), have a ΔHf° value of zero.

Front

What is specific heat capacity?

Back

Specific heat capacity is the amount of heat required to raise the temperature of one gram of a substance by one degree Celsius.

Front

How do you calculate the specific heat capacity?

Back

Specific heat capacity (c) can be calculated using the formula: c = q / (m * ΔT), where q is the heat added, m is the mass, and ΔT is the change in temperature.

Front

What is the unit of heat in the SI system?

Back

The unit of heat in the SI system is the Joule (J).

Front

What is the difference between an open system and a closed system?

Back

An open system can exchange both energy and matter with its surroundings, while a closed system can exchange energy but not matter.

Front

What happens to temperature in an exothermic reaction?

Back

In an exothermic reaction, heat is released to the surroundings, causing the temperature of the surroundings to increase.

Front

What is the formula for calculating heat energy?

Back

The formula for calculating heat energy is q = m * c * ΔT, where q is heat energy, m is mass, c is specific heat capacity, and ΔT is the change in temperature.