Question

1. which of the following would be classified as a homogeneous mixture?

a. orange juice
b. sulfur
c. carbon
d. carbon dioxide

1. an element is a substance which

a. can be broken down into simpler substances by physical means
b. cannot be broken down into simpler substances by physical means
c. can be broken down into simpler substances by physical means
d. cannot be broken down into simpler substances by chemical means

1. a bottle, usually of glass, having a rounded body and a narrow neck is called a

a. graduated cylinder
b. erlenmeyer flask
c. magnifying glass
d. pipette

1. a type of gas burner, commonly used in chemical laboratories, with which a very hot, practically non luminous flame is obtained by allowing air to enter at the base and mix with the gas is called a(n)

a. evaporating dish
b. bunsen burner
c. flame loop
d. diaphragm

1. if you need to measure a liquid by counting drops, you could use a dropper or a

a. flask
b. test tube
c. pipette
d. graduated cylinder

1. a piece of equipment that is used in the lab to evaporate excess liquids is called

a. bunsen burner
b. goggles
c. evaporating dish
d. heater

Explanation:

Question 22

Step1: Recall mixture types

Homogeneous mixtures have uniform composition. Orange juice has pulp (heterogeneous), sulfur and carbon are elements, carbon dioxide is a compound. Wait, no—orange juice without pulp? Wait, no, sulfur (b) is element, carbon (c) element, carbon dioxide (d) compound. Wait, orange juice (a) is a mixture, but is it homogeneous? If it's filtered, maybe, but typically orange juice with pulp is heterogeneous. Wait, maybe the question considers orange juice as homogeneous (like a solution). Wait, no—sulfur is an element (pure substance), carbon element, CO₂ compound. So homogeneous mixture must be a mixture. So orange juice (a) is a mixture, and if it's a solution (like without pulp, uniform), then it's homogeneous. The others are pure substances.

Step2: Eliminate pure substances

Sulfur (b), carbon (c) are elements (pure), CO₂ (d) is compound (pure). So only orange juice (a) is a mixture, and if it's homogeneous (like a solution), then a is correct.

Step1: Define element

An element is a pure substance that cannot be broken down into simpler substances by chemical means (chemical reactions). Physical means don't break substances into simpler chemical substances. So elements can't be broken down chemically.

Step2: Analyze options

a: Elements can't be broken down chemically, so physical means? No. b: "Cannot be broken down... by physical means"—but elements can be separated physically? No, the key is chemical. c: Wrong (can't be broken down chemically). d: Correct—elements can't be broken down into simpler substances by chemical means.

Step1: Recall lab glassware

Graduated cylinder (a) is for measuring volume (straight), Erlenmeyer flask (b) has rounded body and narrow neck, magnifying glass (c) is for magnifying, pipette (d) is for transferring liquid.

Step2: Match description

The description matches Erlenmeyer flask (b). Graduated cylinder is straight, pipette is thin, magnifying glass is not glassware for holding.

Answer:

a. Orange juice

Question 23