Question 1

Given the equation: CH₄ (g)+ 2 O₂ (g)→ CO₂ (g)+ H₂O (l)ΔH = -890.0 kJ The heat liberated when 34.78 grams of methane (CH₄)are burned in an excess amount of oxygen is ________ kJ.

Accepted Answer

The answer of Given the equation: CH₄ (g)+ 2 O₂ (g)→...

Question 2

A 5-ounce cup of raspberry yogurt contains 6.0 g of protein, 2.0 g of fat, and 16.3 g of carbohydrate. The fuel values for protein, fat, and carbohydrate are 17, 38, and 17 kJ/g, respectively. The fuel value of this cup of yogurt is ________ kJ.
A)460
B)520
C)280
D)720
E)72

Accepted Answer

The fuel value is calculated by multiplying the grams of each macronutrient by their respective fuel values and summing them up: (6.0 g protein * 17 kJ/g) + (2.0 g fat * 38 kJ/g) + (16.3 g carbohydrate * 17 kJ/g) = 102 + 76 + 277.1 = 455.1 kJ, which rounds to 460 kJ.

Question 3

When 0.800 grams of NaOH is dissolved in 100.0 grams of water, the temperature of the solution increases from 25.00 °C to 27.06 °C. The amount of heat absorbed by the water is ________ J. (The specific heat of water is 4.18 J/g-°C.)

Accepted Answer

The answer of When 0.800 grams of NaOH is dissolved...

Question 4

The primary component of natural gas is propane.

Accepted Answer

The primary component of natural gas is actually methane, which makes up about 70-90% of its composition. Propane is sometimes present in smaller amounts, but it is not the primary component.

Question 5

Work equals force times distance.

Accepted Answer

This is the formula for calculating work, where work is equal to the force applied multiplied by the distance over which the force is applied.

Question 6

The standard enthalpy change of a reaction is the enthalpy change when all reactants and products are at ________ pressure and a specific temperature.

Accepted Answer

The answer of The standard enthalpy change of a reaction...

Question 7

One joule equals 1 kg-m²/s².

Accepted Answer

One joule is defined as the amount of energy transferred when one newton of force is applied over a distance of one meter, which simplifies to 1 kg·m²/s² in SI units.

Question 8

Petroleum is a liquid composed of hundreds of compounds.

Accepted Answer

Petroleum is a complex mixture of hydrocarbons, which consist of hundreds of different compounds.

Question 9

________ is defined as the energy used to move an object against a force.

Accepted Answer

The answer of ________ is defined as the energy used...

Question 10

Given the equation H₂O (l)→ H₂O (g)ΔH_rxn= 40.7 kJ at 100 °C Calculate the heat required to convert 3.00 grams of liquid water at 100 °C to vapor.

Accepted Answer

The answer of Given the equation H₂O (l)→ H₂O (g)ΔH_rxn=...

Question 11

Given the equation H₂O (l)→ H₂O (g)ΔH_rxn= 40.7 kJ at 100 °C Calculate the mass of liquid water (in grams)at 100 °C that can converted to vapor by absorbing 2400 J of heat.

Accepted Answer

The answer of Given the equation H₂O (l)→ H₂O (g)ΔH_rxn=...

Question 12

Units of energy include newtons, joules, and calories.

Accepted Answer

Newtons are units of force, not energy. Joules and calories are units of energy.

Question 13

Renewable energy sources are essentially inexhaustible.

Accepted Answer

Renewable energy sources such as solar, wind, hydropower, and geothermal are considered to be essentially inexhaustible as they are naturally replenished and will not be depleted over time, unlike non-renewable sources like fossil fuels which are finite and will eventually run out.

Question 14

Coal contains hydrocarbons of high molecular weight as well as compounds containing ________, oxygen, or nitrogen.

Accepted Answer

The answer of Coal contains hydrocarbons of high molecular weight...

Quiz 5: Thermochemistry

Given the equation: CH4 (g)+ 2 O2 (g)→ CO2 (g)+ H2O (l)ΔH = -890.0 kJ The heat liberated when 34.78 grams of methane (CH4)are burned in an excess amount of oxygen is ________ kJ.

A 5-ounce cup of raspberry yogurt contains 6.0 g of protein, 2.0 g of fat, and 16.3 g of carbohydrate. The fuel values for protein, fat, and carbohydrate are 17, 38, and 17 kJ/g, respectively. The fuel value of this cup of yogurt is ________ kJ.