Daniel and Esther Exploring Liquids and Solutions

What is solubility?

• Solubility is the amount of heat a substance can absorb.

• Solubility is the capacity of a substance to dissolve in a solvent.

• Solubility refers to the weight of a substance in a solid state.

• Solubility is the process of a substance changing its state from solid to gas.

Answer explanation

Solubility refers to the capacity of a substance to dissolve in a solvent, making it the correct choice. The other options describe different concepts unrelated to solubility.

Define soluble and insoluble substances.

• Soluble substances dissolve in a solvent; insoluble substances do not.

• Soluble substances are always solid; insoluble substances are always liquid.

• Soluble substances can only be gases; insoluble substances are always solids.

• Soluble substances do not interact with solvents; insoluble substances react with them.

Answer explanation

The correct choice defines soluble substances as those that dissolve in a solvent, while insoluble substances do not dissolve. This is the fundamental distinction between the two categories.

How does temperature affect solubility?

• Higher temperatures always decrease solubility for all substances.

• Solubility is only affected by pressure, not temperature.

• Temperature generally increases the solubility of solids in liquids and decreases the solubility of gases in liquids.

• Temperature has no effect on solubility.

Answer explanation

Temperature generally increases the solubility of solids in liquids because higher energy allows more solute to dissolve. Conversely, it decreases the solubility of gases in liquids due to increased kinetic energy leading to gas escaping.

What is a solution?

• A method of cooking food.

• A means of solving a problem.

• A physical object used for storage.

• A type of mathematical equation.

Answer explanation

A solution is defined as a means of solving a problem, making this the correct choice. The other options refer to cooking methods, storage objects, or mathematical equations, which do not align with the definition of a solution.

Explain how chromatography can be used to separate substances.

• Chromatography relies on chemical reactions to isolate different substances.

• Chromatography uses electrical charges to separate substances in a liquid.

• Chromatography can be used to separate substances by exploiting differences in their movement through a stationary phase when a mobile phase is applied.

• Chromatography separates substances by heating them to high temperatures.

Answer explanation

Chromatography separates substances by utilizing their different rates of movement through a stationary phase when a mobile phase is applied, allowing for effective separation based on physical properties.

Differentiate between a solution and a mixture.

• A solution is homogeneous and consists of a solute dissolved in a solvent, while a mixture can be heterogeneous or homogeneous and consists of physically combined substances.

• A solution can only be made from two solids, while a mixture can include gases.

• A solution is a combination of two or more gases, while a mixture is a single substance.

• A solution is always a solid, while a mixture is always a liquid.

Answer explanation

The correct choice explains that a solution is homogeneous, with a solute in a solvent, while a mixture can be either homogeneous or heterogeneous, consisting of physically combined substances. This distinction is key.

What is the process of separating a mixture called?

• Chemical reaction

• Filtration technique

• Mixture analysis

• Separation process

Answer explanation

The process of separating a mixture is generally referred to as a 'separation process.' This term encompasses various methods, including filtration, but is broader and more accurate than the other options provided.

How can we separate a solvent from a solution?

• Mixing with another solvent.

• Evaporation, distillation, or filtration.

• Sublimation, condensation, or crystallization.

• Adding more solute to the solution.

Answer explanation

To separate a solvent from a solution, methods like evaporation, distillation, or filtration are effective. These techniques utilize physical changes to isolate the solvent, unlike mixing with another solvent or adding more solute.

If a solid in a mixture is magnetic, how can we separate it?

• Dissolve the magnetic solid in water.

• Use a magnet to attract and separate the magnetic solid.

• Use heat to separate the magnetic solid.

• Filter the mixture through a fine mesh.

Answer explanation

To separate a magnetic solid from a mixture, the most effective method is to use a magnet. The magnetic solid will be attracted to the magnet, allowing for easy separation from non-magnetic components.

What is decantation?

• A method of mixing two liquids thoroughly.

• Decantation is a method of separating mixtures by removing a liquid layer from solids or another liquid.

• A process of filtering out impurities from a solid.

• A technique for heating solids to separate them from liquids.

Answer explanation

Decantation is specifically used to separate mixtures by carefully pouring off a liquid layer, leaving behind solids or another liquid. This distinguishes it from mixing, filtering, or heating processes.