What of the following is an advantage of the thermal properties of plastic?(1 point)

Question

Responses

The thermal conductivity of plastic is very high, making it a good material to transmit heat.

Plastics are easy to mold into any shape.

Plastics are safe to use in microwave ovens.

Heating plastics eliminates the risk of BPA exposure.

Answer 1

The correct response regarding an advantage of the thermal properties of plastic is:

Plastics are safe to use in microwave ovens.

This statement highlights a specific thermal property of certain plastics that makes them suitable for reheating food without degrading or releasing harmful substances, as long as they are designed for microwave use.

Answer 2

Which phase change is the opposite of boiling?(1 point)
Responses

freezing

evaporation

melting

condensation

Answer 3

The phase change that is the opposite of boiling is:

condensation.

Boiling involves a substance transitioning from a liquid to a gas, while condensation is the process of a gas turning back into a liquid.

Answer 4

Which table correctly shows the relationships between volume, pressure, and temperature of an enclosed gas?(1 point)
Responses

Quantities Relationship
volume and temperature directly proportional
pressure and volume inversely proportional
pressure and temperature directly proportional.
Quantities Relationship
volume and temperature directly proportional
pressure and volume directly proportional
pressure and temperature inversely proportional.

Quantities Relationship
volume and temperature inversely proportional
pressure and volume directly proportional
pressure and temperature directly proportional.

Quantities Relationship
volume and temperature inversely proportional
pressure and volume inversely proportional
pressure and temperature directly proportional.

Answer 5

The correct table that shows the relationships between volume, pressure, and temperature of an enclosed gas is:

Quantities Relationship
volume and temperature directly proportional
pressure and volume inversely proportional
pressure and temperature directly proportional.

This reflects the fundamental gas laws:

• Charles's Law states that volume and temperature are directly proportional (at constant pressure).
• Boyle's Law states that pressure and volume are inversely proportional (at constant temperature).
• Gay-Lussac's Law states that pressure and temperature are directly proportional (at constant volume).

Answer 6

Which observation is inconsistent with the ideal gas law?(1 point)
Responses

When temperature is held constant and volume increases, the pressure increases.

When nothing is held constant and pressure and volume both increase, the temperature increases.

When pressure is held constant and volume increases, the temperature increases.

When volume is held constant and the temperature increases, the pressure increases.

Answer 7

The observation that is inconsistent with the ideal gas law is:

When temperature is held constant and volume increases, the pressure increases.

This statement contradicts Boyle's Law, which states that at constant temperature, the pressure of a gas is inversely proportional to its volume. Therefore, if the temperature is held constant and the volume increases, the pressure should decrease, not increase.

Answer 8

A gaseous product of a reaction is collected at 280K and 0.95 atm. Given R= 0.0821L⋅atm/mol⋅K, what is the molar mass of the gas, in grams per mole, if 5.49 g of gas occupies 4.92 L?(1 point)
Responses

133 g/mol

0.04 g/mol

24 g/mol

27 g/mol

Answer 9

To find the molar mass of the gas, we can use the Ideal Gas Law equation, which is given by:

\[ PV = nRT \]

Where:

• \( P \) = pressure (in atm)
• \( V \) = volume (in liters)
• \( n \) = number of moles
• \( R \) = ideal gas constant (0.0821 L·atm/(mol·K))
• \( T \) = temperature (in Kelvin)

First, we need to calculate the number of moles \( n \) using the provided values:

Given:

• \( P = 0.95 , \text{atm} \)
• \( V = 4.92 , \text{L} \)
• \( R = 0.0821 , \text{L·atm/(mol·K)} \)
• \( T = 280 , \text{K} \)

We can rearrange the ideal gas law to solve for \( n \):

\[ n = \frac{PV}{RT} \]

Substituting the known values:

\[ n = \frac{(0.95 , \text{atm})(4.92 , \text{L})}{(0.0821 , \text{L·atm/(mol·K)})(280 , \text{K})} \]

Calculating the numerator:

\[ 0.95 \times 4.92 = 4.674 \]

Calculating the denominator:

\[ 0.0821 \times 280 = 22.988 \]

Now calculating \( n \):

\[ n = \frac{4.674}{22.988} \approx 0.203 \]

Now we have the number of moles. The molar mass \( M \) can be found using the formula:

\[ M = \frac{\text{mass}}{n} \]

Given that the mass of the gas is 5.49 g:

\[ M = \frac{5.49 , \text{g}}{0.203 , \text{mol}} \approx 27.0 , \text{g/mol} \]

Thus, the molar mass of the gas is approximately 27 g/mol.

Answer 10

Which statement best describes what it means when something is classified as a strong acid?(1 point)
Responses

It is present in large quantities in a solution.

It resists dissociating into ions in solution.

It is present in low quantities in a solution.

It easily dissociates into ions in solution.

Answer 11

The statement that best describes what it means when something is classified as a strong acid is:

It easily dissociates into ions in solution.

Strong acids completely dissociate into their ions when dissolved in water, leading to a high concentration of hydrogen ions (H⁺) in the solution.