Question

Classify each of the following as a homogeneous or heterogeneous mixture: a. ketchup b. hard-boiled egg c. eye drops

Short answer

a. Homogeneous, b. Heterogeneous, c. Homogeneous

Step-by-step solution

Determine if Ketchup is Homogeneous or Heterogeneous

Examine the characteristics of ketchup. If it appears uniform throughout and the different components are not distinguishable, it's a homogeneous mixture. If it has visible different parts and components that can be separated visually, it's a heterogeneous mixture.

Determine if a Hard-Boiled Egg is Homogeneous or Heterogeneous

Consider the structure of a hard-boiled egg. If the yolk and the white are clearly distinct parts that can be separated, it is a heterogeneous mixture. If it is uniform throughout, it would be considered homogeneous.

Determine if Eye Drops are Homogeneous or Heterogeneous

Analyze the consistency of eye drops. If the solution in the bottle is uniform and appears the same throughout, it is a homogeneous mixture. If there are dispersed particles or layers that are visible, it is a heterogeneous mixture.

Classify Each Mixture

Based on the analysis: (a) Ketchup is a homogeneous mixture because it appears uniform throughout. (b) A hard-boiled egg is a heterogeneous mixture due to the distinguishable yolk and white parts. (c) Eye drops are usually homogeneous mixtures as they are designed to be uniform solutions.

Key concepts

homogeneous mixtures

Homogeneous mixtures are mixtures that have a consistent composition throughout. In these mixtures, the different components are so evenly distributed that they cannot be distinguished with the naked eye. For instance, when you look at ketchup, it gives off a uniform appearance, suggesting that the ingredients are well mixed on a molecular level. Other examples of homogeneous mixtures include:

• Sugar dissolved in water
• Air (a mixture of gases)
• Saltwater

Ketchup appears uniform throughout and does not show distinct parts, making it a homogeneous mixture.

heterogeneous mixtures

Heterogeneous mixtures are combinations of substances that have visibly different components and can be separated physically. These mixtures do not have a uniform composition, and you can see the different parts that make them up. Taking the example of a hard-boiled egg: you can easily see and separate the yolk and the white. This clear separation makes a hard-boiled egg a classic example of a heterogeneous mixture. Other examples include:

• Salad with various ingredients
• Sand mixed with iron filings
• Oil and water

In these mixtures, the different substances maintain their individual properties and can often be separated through simple physical methods.

solution consistency

Solution consistency refers to how uniformly the solutes (substances being dissolved) are distributed within the solvent (the substance doing the dissolving). When the solutes are evenly distributed, the mixture is said to be consistent. Eye drops, for example, are scientifically designed to be consistent so that each drop contains the same concentration of medication. This ensures that users receive an even dose each time. Factors affecting solution consistency include:

• The nature of the solute and solvent
• Temperature
• Agitation or stirring

When the solution is consistent, it is generally a homogeneous mixture, whereas inconsistent distribution of solute and solvent often leads to a heterogeneous mixture.

visual separation

Visual separation is the ability to see distinct parts within a mixture. This is a key characteristic in distinguishing between homogeneous and heterogeneous mixtures. In mixtures like a salad, you can easily see and separate the lettuce, tomatoes, cucumbers, and dressing, making it a heterogeneous mixture. Conversely, in solutions like saltwater, visual separation is not possible as the salt dissolves completely in the water, creating a homogeneous mixture. Factors affecting visual separation include:

• The size and shape of the particles
• The degree of mixing or blending
• The presence of distinct phases (solid, liquid, gas)

By visually examining a mixture, you can often determine whether it is homogeneous or heterogeneous.