7th Grade Study Guide

Definitions

100

pH

  A measure of a solution’s acidity or alkalinity. A pH of 7 is perfectly neutral. Acids have a pH lower than 7; the farther from 7, the stronger the acid. Alkaline solutions, called bases, have a pH higher than 7; again, the farther above 7, the stronger the base.

200

Acidification

 A process that lowers the pH of a solution. When carbon dioxide dissolves in water, it triggers chemical reactions that create carbonic acid.

300

Acids

A substance with a pH level of 0-7

400

Bases

A substance with a pH level of 7-14

500

Litmus Paper/pH strips

Determines the pH level of a substance 

Acids

100

What is a possible pH level for an Acid

0-7

200

What color do acids turn litmus paper

Red

300

How do acids taste

Sour

400

What would a substance with a pH of 1 be described as

A strong base

500

What would a substance with a pH of 5.5 be described as

A weak acid

Bases

100

What is a possible pH level for a Base

7-14

200

What color do bases turn litmus paper

Blue

300

How do bases taste

Bitter

400

What would a substance with a pH of 14 be described as

A strong base

500

What would a substance with a pH of 10 be described as

A weak base

Chemical Equations

100

_SnO₂ + _H₂ = _Sn + _H₂0

SnO₂ + 2 H₂ = Sn + 2 H₂0

200

_KOH +_H₃PO₄ = _K₃PO₄ + _H₂O

3 KOH +H₃PO₄ = K₃PO₄ + 3 H₂O

300

_KNO_3 + _H₂CO₃ = _K₂CO₃ + _HNO₃

2 KNO_3 + H₂CO₃ = K₂CO₃ + 2 HNO₃

400

_Agl + _Na₂S = _Ag₂S + _Nal

2 Agl + Na₂S = Ag₂S + 2 Nal

500

_Ba₃N₂ + _H₂O = _Ba(OH)₂ + _NH₃

Ba₃N₂ + 6 H₂O = 3 Ba(OH)₂ + 2 NH₃