Science test Unit 11

test 5/19/26

Where is a superscript?

Positioned above the letter

Where a subscript?

Positioned below the letter

Where is the coefficient?

The numbers in front of the letter.

The reactants are on the ___ side of the equation

Left

The products are on the ___ side of the equation

Right

What is the arrow used for in chemical equations?

It shows that it’s equal and that chemically reacts to form.

What kind of equation is this: 2KCLO3 —> 2KCL + 3O2

Decompsiton

What kind of equation is this: CaO + H20 —> Ca(OH)2

Synthesis

What kind of equation is this: C3H8 + 5O2 —> 3CO2 + 4H2O

Combustion

What kind of equation is this: Zn + 2HCl —> ZnCl2 + H2

Replacement

Predict whether the product is a neutral, acid, or base: Acid= 4, Base= 11

Base

Predict whether the product is a neutral, acid, or base: Acid= 1, Base= 7.5

Acid

Predict whether the product is a neutral, acid, or base: Acid=6 Base=8

Neutral

Predict whether the product is a neutral, acid, or base: Acid=2 Base=14

Base

Predict whether the product is a neutral, acid, or base: Acid=5.5 Base=14

Base

What 2 numbers have the most acid (there’s more but these two are the most acidic)

0 & 1

What 2 numbers have the most base (there’s more but these two are the most basic/ alkaline)

13 & 14

In a chemical reaction:

Bonds BREAK, atoms RE-ARRANGE, and NEW bonds form

Evidence that a chemical reaction is exothermic includes:

Temperature change

Because of ______, the number and type of element in the reactant must equal the number and type of elements in the product

The Law of Conservation of Mass

In an ice pack, ammonium nitrate is dissolved in water and absorbs heat, making the pack cold. This is an example of what type of reaction?

Endothermic

When an acid and base start to react to neutralize each other, they produce:

Salt and H2O

When iron and oxygen react to form rust, it produces a significant amount of heat. This is an example of what type of reaction?

Exothermic

An acid-base reaction is what type of chemical reaction?

Replacement

Precipitates are formed through this type of chemical reaction:

Replacement

This type of chemical reaction is typically spontaneous and exothermic:

Synthesis

Exothermic= ?? and Endothermic= ??

Synthesis and decomposition

This type of chemical reaction is typically endothermic, requiring light, heat, or electricity to make them happen:

Decomposition

A catalyst _____ because ____

Speeds up a reaction/ increases the energy to break bonds

A catalyst is not included in the chemical equation because:

It is not consumed, produced, or chemically altered

To prove that a chemical reaction is exothermic or endothermic, you could:

Measure the change in temperature

A salt is:

A product from acid-base reaction

Why does water self- ionize, ad what two ions come from H2O?

It ionizes because it is extremely polar- it produces hydronium (H3O+) and Hydroxide (OH-)

Neutral solution:

H30+ = OH-

Acidic solution:

H3O+ > OH-

Basic/ alkaline solution:

H3O+ < OH-