Question

1. classify the following as heterogeneous or as homogeneous: sand & salt mixture hydrogen iron salt water unfiltered air iron with rust pure water an apple nitric acid tossed salad granite wood 15. classify the following as an element, a compound, a solution, or a heterogeneous mixture: aluminum raisin bread carbon dioxide water sugar and water sulfur sulfuric acid mercury an orange water & instant coffee a pencil carbon particles & sugar nitrogen air gasoline grain alcohol

Explanation:

Step1: Recall definitions

A homogeneous mixture has uniform composition, a heterogeneous mixture has non - uniform composition. An element is made of one type of atom, a compound is made of different types of atoms chemically bonded, and a solution is a homogeneous mixture.

Step2: Classify for question 14

• Sand & salt mixture: Heterogeneous (visible different components).
• Hydrogen: Homogeneous (element, pure substance).
• Iron: Homogeneous (element, pure substance).
• Salt water: Homogeneous (solution).
• Unfiltered air: Homogeneous (mixture of gases with uniform composition).
• Iron with rust: Heterogeneous (rust is a different compound on iron).
• Pure water: Homogeneous (compound).
• An apple: Heterogeneous (different parts like skin, flesh, seeds).
• Nitric acid: Homogeneous (compound).
• Tossed salad: Heterogeneous (different vegetables).
• Granite: Heterogeneous (visible different minerals).
• Wood: Heterogeneous (different cellular structures).

Step3: Classify for question 15

• Aluminum: Element.
• Raisin bread: Heterogeneous mixture.
• Carbon dioxide: Compound.
• Water: Compound.
• Sugar and water: Solution.
• Sulfur: Element.
• Sulfuric acid: Compound.
• Mercury: Element.
• An orange: Heterogeneous mixture.
• Water & instant coffee: Solution.
• A pencil: Heterogeneous mixture (wood, graphite, eraser etc.).
• Carbon particles & sugar: Heterogeneous mixture.
• Nitrogen: Element.
• Air: Solution (homogeneous mixture of gases).
• Gasoline: Solution (homogeneous mixture of hydrocarbons).
• Grain alcohol: Compound.

Answer:

Question 14:
Sand & salt mixture: Heterogeneous
Hydrogen: Homogeneous
Iron: Homogeneous
Salt water: Homogeneous
Unfiltered air: Homogeneous
Iron with rust: Heterogeneous
Pure water: Homogeneous
An apple: Heterogeneous
Nitric acid: Homogeneous
Tossed salad: Heterogeneous
Granite: Heterogeneous
Wood: Heterogeneous

Question 15:
Aluminum: Element
Raisin bread: Heterogeneous mixture
Carbon dioxide: Compound
Water: Compound
Sugar and water: Solution
Sulfur: Element
Sulfuric acid: Compound
Mercury: Element
An orange: Heterogeneous mixture
Water & instant coffee: Solution
A pencil: Heterogeneous mixture
Carbon particles & sugar: Heterogeneous mixture
Nitrogen: Element
Air: Solution
Gasoline: Solution
Grain alcohol: Compound