Compounds 1
Compounds have properties __________ from their individual elements
different
___________ are the only way to form compounds
Chemical reactions
What happens when you mix an acid with a base?
It produces a salt plus water
What color litmus do acids and bases turn into?
acid = blue -> red
base = red -> blue
What has pH of 7?
_____ chemical changes are reversible, or they can be undone
Most
What is a precipitate?
A solid formed from the chemical reaction of some solutions
What are the prefixes used to indicate the number of atoms in a compound.
1: ?
2: ?
3: ?
1: mon
2: di or bi
3. tri
What colors do hydrangea flowers become in soils with acids or bases?
acid -> blue flowers
base -> pink flowers
What kind of ions do bases make in water?
What kind of ions do acids make in water?
Hydroxide ions (OH-)
hydronium ions (H3O+)
Why do compounds have new and different properties?
The joining of the atoms is what causes it.
What are the 5 signs of chemical change?
1. changes color
2. forms tarnish
3. releases gas
4. forms a precipitate
5. releases energy
2H2 + O2 = 2H2O
What is this called?
For what compound?
What is the left side called?
What is the right side called?
Chemical equation
Water
Reactants
Products
What kinds of acids do humans and some animals have in their stomachs? (chemical name and formula)
What is it for?
Hydrochloric acid (HCl)
Helps animals digest food
What special substance do scientists us to identify acids and bases?
Where do they come from? What is it called?
Indicators
Litmust is a dye obtained from lichens
________ is a compound formed when iron in the spoon combines with oxygen in the air
What is its chemical formula?
What is its chemical name?
Rust
Fe2O3
Iron oxide
Fill in the blank.
The law of ____________ of mass
The _____________ of the reactant equals the ____________ of the product in a _________
conservation
total mass; total mass; chemical reaction
What are the properties of acids?
Give 2 examples.
1. tastes sour and burns if you touch it
2. makes blue litmust turn red
3. reacts with metals to make hydrogen gas
ex) vinegar, lemon juice, cream of tartar solution, juice from an onion, and coca cola
What is the scale used to measure acidity and alkalinity?
What does it stand for?
What is the range?
What does each end of the range mean?
pH scale
potential for Hydrogen
1-14
1 -> very acidic
14 -> very alkaline
What are the properties of bases?
Give 2 examples.
1. tastes bitter
2. feels soapy
3. makes red litmus turn blue
ex) soap, drain cleaners, ammonia, sodum hydroxide (lye), baking soda in water, milk of magnesia, milk, and herbal tea
Give an example of each of the 5 signs of chemical change.
1. changes color
- bleach removes the color from clothing
2. forms tarnish
- metals react to oxygen and corrode
3. releases gas
- an antacid reacts with water, bubbles of carbon dioxide gas form
4. forms a precipitate
- "soap scum" a precipitate formed from solutions of soap and water
5. releases energy
- burning a candle releases light or heat
What is the product of this equation?
NaHCO3 + HC2H3O2 = ?
H2O + CO2 + NaC2H3O2
HCl + NaOH = ?
What is the product of this equation? (chemical formula)
What are the chemical names of each individual formula?
NaCl + H2O
reactants: hydrochloric acid + sodium hydroxide (base)
products: sodium chloride (table salt) + water
What do acids, bases, and salts give off in water?
What do ions do in solutions?
What do you call solutions like this?
Ions
Give off electricity
Electrolytes
What are the properties of salt? (4)
1. have a high melting point
2. form crystals made of ions
3. tend to be hard and brittle
4. some dissolve in water