Chemical Reactions

Evidence of a Reaction

100

True or false: Chemistry is the study of matter and how matter changes with reactions.

True

200

Mention 3 evidences that indicate a chemical reaction takes place.

Gas, color, change in properties (substrate) and overall production of one or more new substances, precipitate?

300

This solid forms from a solution during a chemical reaction.

What is a precipitate?

400

True or false: a chemical reaction may be detected by observing changes in the properties of matter.

What is true?

500

There is a lit candle, the wax has melted down the side and hardened on your table. The type of change that the wax has gone through chemical or physical change. Which one? 

Physical change.

Part of a Chemical Reaction

100

Parts on the right side of a chemical equation is called?

Product

200

Parts on the left side of a chemical equation is called?

Reactant

300

Balance: Mg + O2 ----> MgO

2Mg + O2 ----> 2MgO

400

chemical reactions in which the reactants absorb heat energy from the surroundings to form products is _____

Endothermic Reaction

500

True or false.. The amount of matter in a chemical reaction changes...

False

Types of reactions

100

Balance and classify: NaOH(s)→Na2O(s)+H2O(g)

2NaOH(s)→Na2O(s)+H2O(g)
Decomposition

200

The type of reaction where one element or two replace each other or 2 elements trade places.

Replacement reaction

300

The type of reaction where more complex compounds are formed from simple ones.

What is a synthesis reaction?

400

Balance and Classify: Fe(s)+O2(g)→Fe2O3(s)

4Fe(s)+3O2(g)→2Fe2O3(s), Synthesis or combination

500

Balance and Classify: HCl(aq)+NaOH(aq)→NaCl(aq)+H2O(l)

Already balance & Double replacement.

Random

100

NaCN(aq)+HBr(aq)→NaMg(aq)+HCN(g)

NaCN(aq)+HBr(aq)→Na(Mg) it should Br(aq)+HCN(g)

200

The minimal amount of energy needed to start a reaction.

What is activation energy?

300

True/False: The rate of a chemical reaction is independent of temperature.

What is false? Temp can change everything including the rate of the reaction.

400

 Balance: Na2S(aq)+HCl(aq)→NaCl(aq)+H2S(g)

Na2S(aq)+2HCl(aq)→2NaCl(aq)+H2S(g)

500

The best evidence of Chemical reaction is?

The formation of a new substance.