Chemical Reactions

Front

What kind of reaction occurred in the cold pack when Carla applied it to Maria's ankle?

Back

It is a chemical change because heat energy is absorbed and the pack gets colder.

Front

Which of these does NOT demonstrate a chemical change?

• Burning sugar
• The rusting of steel wool
• Making soap by allowing fat to react with sodium hydroxide
• Measuring the freezing point of different concentrations of salt water

Back

Measuring the freezing point of different concentrations of salt water

Front

A scoop of baking soda is added to a beaker containing vinegar. The baking soda disappears and bubbles are observed. This is an example of a _____________ change.

Back

chemical

Front

What can students use to distinguish pure substances, such as elements and compounds with a constant composition, from other substances?

Back

Density

Front

What happened to the rest of the mass of the leaves after burning?

Back

It was turned into smoke and gas.

Front

What is common to all chemical changes?

Back

A new substance is produced.

Front

What kind of property is demonstrated when burning steel wool, and how do you know?

Back

Burning steel wool demonstrates a chemical property, flammability.

Front

Which image displays a chemical property about a substance?

Back

II and IV

Front

Evidence that a chemical change occurred when mixing substances would NOT include: producing a gas, change in color, change in shape, change in temperature.

Back

change in shape.

Front

Which experiment demonstrates a chemical property?

Options: Measure the pH of different household chemicals, Form a density column using common household materials, Measure the melting point of common household chemicals, Measure the solubility of different household substances.

Back

Measure the pH of different household chemicals