Chemical Changes - Chapter 7

These flashcards cover key concepts related to chemical changes, conservation of mass and energy, methods for making salts, displacement reactions, and rates of reaction.

What does conservation of mass in a chemical reaction state?

Mass before and after a reaction remains the same (conserved).

What is the general equation for making salts from metal and acid?

Acid + metal → salt + hydrogen.

What is a displacement reaction?

A chemical reaction where a more reactive element replaces a less reactive element in a compound.

How do smaller pieces affect the rate of reaction?

Smaller pieces have more surface area, allowing them to react faster than larger pieces.

What happens to the rate of reaction when the temperature increases?

The reaction happens faster because more energy is available for collisions.

What is the definition of exothermic reactions?

Reactions that release heat and make the surrounding warmer.

In the context of chemical reactions, what does concentration refer to?

The amount of particles available for collisions; higher concentration leads to faster reactions.

What did the phlogiston theory propose?

That substances contain phlogiston which is released when burned.

What is the formula for hydrochloric acid?

HCl.

What is the symbol equation for the reaction of copper carbonate decomposing?

CuCO3 → CuO + CO2.