First 6 Weeks Review

A student is measuring the properties of a sample of ethanol. Which is an extensive property of the sample?

• mass
• color
• density
• boiling point

Which statement describes a physical change?

• An iron bolt on a bridge rusts and weakens the bridge.
• A piece of paper burns when lit with a match.
• A balloon artist twists a long balloon into a shape of an animal.
• Slivers of magnesium in fireworks form a bright glow as they burn.

In which two groups are mixtures classified?

• Heterogeneous and homogeneous
• Solid and liquid
• Liquid and gaseous
• Elements and compounds

Which set is an example of an element, a compound, and a mixture?

• Carbon, oxygen, carbon dioxide
• Pure water, river water, sea water
• . Oxygen, Earth's atmosphere, orange juice
• Nitrogen, table sugar, cough syrup

Which is the main difference between physical changes and chemical changes?

• A physical change forms one or more new substances but a chemical change does not.
• A chemical change forms one or more new substances but a physical change does not.
• Substances change state of matter only by undergoing physical changes, not chemical changes.
• None of the answers listed

Which of the following is a physical change?

• corrosion
• explosion
• evaporation
• rotting of food

Which of the following can be classified as a mixture?

• pure water
• pure air
• pure nitrogen
• pure gold

What is average atomic mass of Bromine if 9.6% exists as ⁷⁹Br  and 90.4% exists as  ⁸⁰Br ?

• 79.04 g
• 79.54
• 79.14
• 79.90

Which type of radioactive decay has the fastest, most energetic radiation?

• alpha
• beta
• gamma

What is the missing product in the above nuclear reaction?

• ²³⁰Ra
• ²³⁸Ra
• ²³⁰U
• ²³⁸U