Question

draw simple graphs that show the relationship between temperature and solubility (for liquid and solid solutes) and pressure and solubility (for gas solutes).

Explanation:

1. Temperature vs. Solubility (Liquid and Solid Solutes)

For most solid and liquid solutes, solubility generally increases with an increase in temperature. We can represent this with a simple line graph.

• X - axis (Independent Variable): Temperature (in °C or K)
• Y - axis (Dependent Variable): Solubility (in g of solute per 100 g of solvent or other appropriate solubility units)

Step 1: Plot the Axes

Draw the X - axis (labeled "Temperature") and the Y - axis (labeled "Solubility").

Step 2: Determine the Trend

Since solubility of most solids/liquids increases with temperature, we draw a line that starts from the lower left (lower temperature, lower solubility) and goes towards the upper right (higher temperature, higher solubility). For example, if we consider the solubility of potassium nitrate ($KNO_3$) in water, at 0°C, its solubility is around 13 g/100 g water, and at 100°C, it is around 246 g/100 g water. We can mark a few points (e.g., (0, 13), (20, 32), (40, 64), (60, 110), (80, 169), (100, 246)) and then draw a smooth curve (or a line for simplicity) connecting these points.

2. Pressure vs. Solubility (Gas Solutes)

According to Henry's Law, the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas above the liquid, provided the temperature is constant. We can represent this with a simple line graph.

• X - axis (Independent Variable): Pressure (in atm or kPa)
• Y - axis (Dependent Variable): Solubility (in g of gas per 100 g of solvent or other appropriate solubility units)

Step 1: Plot the Axes

Draw the X - axis (labeled "Pressure") and the Y - axis (labeled "Solubility").

Step 2: Determine the Trend

Since solubility of a gas is directly proportional to pressure (at constant temperature), we draw a straight line passing through the origin (or near the origin if there is a small solubility at very low pressure) with a positive slope. For example, for carbon dioxide ($CO_2$) dissolving in water, as the pressure of $CO_2$ above the water increases, the amount of $CO_2$ that can dissolve in water (its solubility) also increases. If we consider pressure in atm and solubility in g/L, at 1 atm, the solubility of $CO_2$ in water at 20°C is about 0.169 g/L, and at 2 atm, it is about 0.338 g/L (assuming ideal behavior according to Henry's Law, $S = k_H\times P$, where $S$ is solubility, $k_H$ is Henry's Law constant, and $P$ is pressure). We can mark points like (1, 0.169), (2, 0.338), (3, 0.507) and draw a straight line through these points.

Final Graph Descriptions

• Temperature - Solubility (Solids/Liquids): A line graph with temperature on the x - axis, solubility on the y - axis, and a curve (or line) with a positive slope (increasing from left to right).
• Pressure - Solubility (Gases): A line graph with pressure on the x - axis, solubility on the y - axis, and a straight line with a positive slope (passing through or near the origin).

(Note: If you want to represent the graphs in a more formal way, you can use graph - drawing software, but the above steps describe how to sketch them by hand.)

Answer:

According to Henry's Law, the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas above the liquid, provided the temperature is constant. We can represent this with a simple line graph.

• X - axis (Independent Variable): Pressure (in atm or kPa)
• Y - axis (Dependent Variable): Solubility (in g of gas per 100 g of solvent or other appropriate solubility units)

Step 1: Plot the Axes

Draw the X - axis (labeled "Pressure") and the Y - axis (labeled "Solubility").

Step 2: Determine the Trend

Since solubility of a gas is directly proportional to pressure (at constant temperature), we draw a straight line passing through the origin (or near the origin if there is a small solubility at very low pressure) with a positive slope. For example, for carbon dioxide ($CO_2$) dissolving in water, as the pressure of $CO_2$ above the water increases, the amount of $CO_2$ that can dissolve in water (its solubility) also increases. If we consider pressure in atm and solubility in g/L, at 1 atm, the solubility of $CO_2$ in water at 20°C is about 0.169 g/L, and at 2 atm, it is about 0.338 g/L (assuming ideal behavior according to Henry's Law, $S = k_H\times P$, where $S$ is solubility, $k_H$ is Henry's Law constant, and $P$ is pressure). We can mark points like (1, 0.169), (2, 0.338), (3, 0.507) and draw a straight line through these points.

Final Graph Descriptions

• Temperature - Solubility (Solids/Liquids): A line graph with temperature on the x - axis, solubility on the y - axis, and a curve (or line) with a positive slope (increasing from left to right).
• Pressure - Solubility (Gases): A line graph with pressure on the x - axis, solubility on the y - axis, and a straight line with a positive slope (passing through or near the origin).

(Note: If you want to represent the graphs in a more formal way, you can use graph - drawing software, but the above steps describe how to sketch them by hand.)