The table below displays four solutions made by dissolving salt in water.

Question

Solution Mass of NaCl (g) Volume of water (ml)

A

5.0

50.0

B

5.0

75.0

C

5.0

100,0

D

5.0

125.0

Which of the solutions has the highest concentration of salt?

(1 point)

Solution D

Solution B

Solution A

Solution C

Answer 1

To find the concentration of salt in each solution, we calculate the concentration of NaCl in grams per milliliter (g/mL) using the formula:

\[ \text{Concentration} = \frac{\text{Mass of NaCl}}{\text{Volume of water}} \]

Now, let's calculate the concentrations for each solution:

• Solution A: \[ \text{Concentration} = \frac{5.0 , \text{g}}{50.0 , \text{mL}} = 0.1 , \text{g/mL} \]

• Solution B: \[ \text{Concentration} = \frac{5.0 , \text{g}}{75.0 , \text{mL}} \approx 0.0667 , \text{g/mL} \]

• Solution C: \[ \text{Concentration} = \frac{5.0 , \text{g}}{100.0 , \text{mL}} = 0.05 , \text{g/mL} \]

• Solution D: \[ \text{Concentration} = \frac{5.0 , \text{g}}{125.0 , \text{mL}} = 0.04 , \text{g/mL} \]

Now, we compare the concentrations:

• Solution A: 0.1 g/mL
• Solution B: 0.0667 g/mL
• Solution C: 0.05 g/mL
• Solution D: 0.04 g/mL

The solution with the highest concentration of salt is Solution A.

Answer 2

A?

Answer 3

Yes, that's correct! Solution A has the highest concentration of salt (NaCl) at 0.1 g/mL. The other solutions have lower concentrations due to the same mass of salt being dissolved in larger volumes of water. So, the answer is indeed Solution A.

Answer 4

Four students in a physical science class are testing various methods for dissolving laundry soap in water. Each student mixes 20 grams of soap with 1000 mL of water. The table displays the different methods used by each student

Form of Soap

Water Temperature

Student

Method of Combination

solid cube

Darien

50°C

no stirring

vigorous stirring

Heather

powder

105°C

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solid cube

Abdullah

gentle stirring

50°C

Larissa

powder 75°C

gentle stirring

Which of the following represents the most likely order in which the students' laundry soap dissolved, from the first to the last?Which of the following represents the most likely order in which the students' laundr dissolved, from the first to the last?

(1 point)

Heather

Larissa

Abdullah

Darien

Darien

Abdullah

Larissa

Heather

Larissa

Abdullah

Heather

Darien

Abdullah

Darien

Heather

Larissa

Answer 5

To determine the order in which the students' laundry soap dissolved, we must consider the factors that affect the rate of dissolution, which include:

1. Form of Soap: Powders generally dissolve faster than solid cubes.
2. Water Temperature: Higher temperatures typically increase the solubility and rate of dissolution.
3. Stirring Method: Vigorous stirring promotes faster dissolution compared to no stirring or gentle stirring.

Based on the criteria above, here’s the analysis of each student:

• Heather: Uses powder with water at 105°C and vigorous stirring. This would likely dissolve the fastest.

• Larissa: Uses powder with water at 75°C and gentle stirring. This is slower than Heather but faster than a solid cube.

• Abdullah: Uses a solid cube with water at 50°C and gentle stirring. This will be slower than without stirring, especially because a solid cube is involved.

• Darien: Uses a solid cube at 50°C with no stirring, which is likely to dissolve the slowest because it has the lowest temperature and no stirring.

Putting it all together, the most likely order from first to last dissolution would be:

1. Heather (Powder, 105°C, vigorous stirring)
2. Larissa (Powder, 75°C, gentle stirring)
3. Abdullah (Solid cube, 50°C, gentle stirring)
4. Darien (Solid cube, 50°C, no stirring)

So, the correct order is: Heather, Larissa, Abdullah, Darien.

Answer 6

This graph illustrates how the solubility of various gases in water changes with temperatur

Solubility (mg/100 g H₂O)

10

8

6

4

2

NO

0,

CO

CH

-N

0 10 20 30

40

Temperature (°C)

According to this graph, which of the following most accurately characterizes the solubility these gases?

(1 point)

Gases composed of a single element are more soluble at higher temperatures.

Gases made up of multiple elements are more soluble at lower temperatures.

All of these gases become more soluble at higher temperatures.

Answer 7

To accurately assess the solubility of the gases based on the given graph, we can analyze the general trend of solubility with respect to temperature:

1. Gases composed of a single element: This statement is too broad and does not accurately reflect the solubility trend without specific data from the graph.

2. Gases made up of multiple elements are more soluble at lower temperatures: This generally describes the trend seen in many gas solubility graphs, particularly for gases like CO₂. However, without the specific gases and their solubility data mentioned in the question, we cannot confirm this statement as universally true.

3. All of these gases become more soluble at higher temperatures: This statement is usually false for gases. In most cases, gas solubility in water decreases with an increase in temperature. Typically, as temperature increases, gases tend to escape from the solution more easily.

Given these considerations, the most accurate characterization based on general principles of gas solubility is:

Gases made up of multiple elements are more soluble at lower temperatures.

If the graph shows a typical trend for gases, then higher temperatures would generally lead to reduced solubility. However, if you have the visual representation of the graph or any specific data points for the gases (like individual solubility at different temperatures), that information would further clarify the statements.

Answer 8

The diagram below illustrates the structure of a chemical. Which of the following most accurately describes the type of molecule depicted in the image?

[Na] [OH]

(1 point)

This chemical is a base because it can release OH' ions.

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This chemical is an acid because it can release OH- ions.

This chemical is a base because it can release Hions.

This chemical is an acid because it can release Hions.

Answer 9

The structure depicted in your notation suggests the presence of sodium (Na) and hydroxide (OH⁻) ions. This indicates that you are likely referring to sodium hydroxide (NaOH).

To analyze the options:

1. This chemical is a base because it can release OH⁻ ions.

   • This is correct. Sodium hydroxide is a strong base because it dissociates in water to release hydroxide ions (OH⁻).

2. This chemical is an acid because it can release OH⁻ ions.

   • This is incorrect. Acidic substances do not release OH⁻ ions; they typically release H⁺ ions (protons).

3. This chemical is a base because it can release H⁺ ions.

   • This is incorrect. Bases do not release H⁺ ions; they either accept H⁺ ions or release OH⁻ ions.

4. This chemical is an acid because it can release H⁺ ions.

   • This is incorrect. As mentioned earlier, acids release H⁺ ions, not OH⁻ ions.

Based on this analysis, the most accurate statement is: This chemical is a base because it can release OH⁻ ions.