general chemistry

What is a pure substance?

• A combination of different substances

• Can be separated through physical means

• Can be separated through chemical means and results in elements and compounds

• Always a mixture

Which of the following is a mixture?

• Water (H₂O)

• Iron fillings (Fe)

• Concrete

• Acetylene (C₂H₂)

What is an example of a homogeneous mixture?

• Sand and water

• Orange juice with pulp

• Air inside a balloon

• Soil

Which of the following is a compound?l

• Aluminum (Al)

• Magnesium (Mg)

• Ethanol (C₂H₅OH)

• Soil

What is an example of a heterogeneous mixture?

• Tap water in a glass

• Muddy water

• Salt + pure water (NaCl + H₂O)

• Sugar + pure water

What is the process of separating a heterogeneous mixture using a filter called?

• Decantation

• Centrifugation

• Filtration

• Magnetic separation

Which of the following is an element?

• Concrete

• Limestone

• Aluminum

• Ethanol

What type of mixture is blood?

• Homogeneous

• Heterogeneous

• Pure substance

• Compound

Which method is used to separate a solid from a liquid by evaporating the liquid?

• Filtration

• Distillation

• Centrifugation

• Chromatography

What is an example of a pure substance?

• Tap water

• Baking soda

• Soil

• Blood