Question

a. a solution of two solids
b. a mixture of particles with different densities
c. a mixture of particles of different sizes
d. a mixture of magnetic and nonmagnetic items

1. the figure shows physical and chemical changes as someone prepares an egg. which is a correct statement about one step in this process?

image of hands cracking an egg into a pan

a. as the shell cracks, a new type of matter forms.
b. as the egg cooks, a new type of matter forms.
c. the total weight of the eggshell changes as it cracks into pieces.
d. the total volume of the egg changes as the egg is poured from the shell into the pan.

1. what is one difference between a mixture and a compound?

a. a compound can only be separated into its components by chemical means.
b. a mixture must be uniform in composition

Explanation:

Question 25

• Option a: Cracking a shell is a physical change (breaking the shell), no new matter forms. So a is wrong.
• Option b: Cooking an egg involves denaturation of proteins, a chemical change, so new matter (cooked egg structure) forms. This is correct.
• Option c: Cracking the shell is a physical change, mass (weight) is conserved. So c is wrong.
• Option d: Pouring the egg is a physical change, volume of the egg (the substance) doesn't change (just its shape/container). So d is wrong.

• Option a: Compounds are chemically bonded, so to separate components, chemical reactions (means) are needed (e.g., electrolysis of water to get H₂ and O₂). Mixtures can be separated by physical means (like filtration, distillation). This is correct.
• Option b: Mixtures can be heterogeneous (non - uniform, like sand and water) or homogeneous (uniform, like salt water). So a mixture doesn't have to be uniform. Thus, b is wrong.

Answer:

b. As the egg cooks, a new type of matter forms.

Question 26