Chemical Reaction Quizizz Notes

Chemical Reactions

Objective: Identify signs of a chemical reaction.

Multiple Choice

What do you think happens in a chemical reaction?

• The atoms of the reactants always stay together to form the products
• The atoms of the reactants unbond, rearrange, and then rebond to form the products
• New atoms are formed which combine to make the products
• Some atoms disappear while others multiply to form the products

Signs of a Chemical Change

https://www.youtube.com/watch?v=q76UNX3otvA

Indicators of a Chemical Reaction

• Formation of a gas

• Formation of a precipitate

• Change in color

• Change in temperature without heating or cooling it

• Production of light

• Production of an odor

Multiple Select

Check ALL the boxes that show the signs of a chemical change.

• sound and smell

• air

• color change

• gas (bubbles) produced

• forces

Multiple Choice

Which of the following is an example that includes evidence of a chemical reaction?

• A sample of zinc is placed in water and it settles to the bottom
• A solid block of ice is heated and it completely melts into a liquid. 
• Sugar that is burned gives off an odor and turns brown and then black.
• A tomato is placed into a blender and chopped up into smaller pieces.

Multiple Choice

A clear liquid from a flask is poured into another clear liquid in a beaker. Which of the following results of this procedure would indicate a new substance was formed?

• The level of the substance in the beaker is higher after the other liquid is added.
• A yellow solid forms and then settles to the bottom of the beaker.
• Small white crystals are left behind in the flask that held the first liquid.
• The mass of the combined liquids is greater than either original liquid.

Multiple Choice

Four students performed four different investigations by combining different substances. Which of the observations is most indicative of a chemical reaction?

• investigation 1
• investigation 2
• investigation 3
• investigation 4

https://www.youtube.com/watch?v=2EQznGPZY5A

Multiple Choice

Which is the name of the kind of solid substance formed in this figure?

• color change

• precipitate

• acid

• chemicals

What are reagents, reactants, and products?

• Reactants and reagents are the substances that are used to bring about the chemical reaction

•  A reactant is any substance that is consumed or used up during the reaction.

• The substance that is produced by a chemical reaction is called the product.

​Reactants

​Products

​"reacts with"

"yields" or "forms"

Multiple Choice

What is the arrow in a chemical equation...

H_{2 +} O --> H₂O

• Reactants

• Products

• Yields

• Chemical Equation

Multiple Choice

The blue numbers in the image below represent ________

• I don't know, and don't want to try
• coefficients
• subscripts
• none of the answers are correct

Multiple Choice

What is the part of the chemical equation in green called? 
Fe + S --> FeS

• products
• reactants
• yield
• chemical formula

Multiple Select

In a chemical equation, the +  means ______. More than one answer may be right.

• plus

• reacts with

• becomes

• yields

Multiple Choice

The left side of the equation below is called

• Products
• Reactants

Multiple Choice

When an italics lower case aq, (aq), is found beside a chemical in an equation it indicates that the chemical is _____________.

• liquid

• a precipitate in water

• dissolved in water

• gaseous

Multiple Choice

When an italics lower case g, (g), is found beside a chemical in an equation it indicates that the chemical is _____________.

• liquid

• insouble

• soluble

• gaseous

Reaction Rate

• Some happen very quickly like explosions, while others can take a long time, like metal rusting. 

• The reaction rate can be changed by adding energy, a catalyst, or changing the particle size.

• Increasing the concentration or pressure of the reactants can speed up the reaction rate.