Chemistry Flashcards
A bright yellow solid substance is known to be an element. It is brittle and will hatter if hit with a hammer. It is a poor conductor of electricity. This element is best known as
A nonmetal
An atom becomes an ion with a charge of +2 when it
Loses two electrons
An atom becomes negatively charged when it
Gains electrons
A chemical change is distinguished from a physical change because in a chemical Change the original substance changes its
Composition
A gas is proved to be carbon dioxide if
Like water goes milky when shaken with the gas
A gas can be proven to be oxygen if by means of
A glowing splint bursts into flame
In a periodic table elements with similar properties are grouped in
Vertical columns
Group of elements with only non metals
Cl, S, P
A solid element looks silvery and shiny when it’s surface has been freshly sanded and polished. It will stretch if enough force is applied. This element is
A metal
Set of only metals
Zn, Li, Ca
When a burning splint pops at the mouth of a test tube which element is present
Hydrogen
When two non metal combine it is called a
Molecular compound
A combustion reaction produces
Water and carbon dioxide
Double displacement
Couples switching partners
Single displacement
Couple dancing someone cuts in
In a chemical reaction the total mass of the reactants is always equal to total mass of products. This is known as the
Law of conservation of mass
If bacl2 and na2so4 combine a
Double displacement reaction occurs
What does the —> mean in an equation
To produce
What does the + mean in an equation
Reacts with
When drano is added to a blocked drain heat is produced as a reaction. This is called an
Exothermic reaction
The speed at which a chemical reaction occurs is called
Rate of reaction
An example of an endothermic reaction
Melting a sample of ice
An exothermic reaction is one where
Heat is given off
A neutral solution has a ph of
7
An acid base indicator is a substance that
Turns different colors in acids as bases
An acid
Tastes sour
A solution has a ph of 8 . This solution is best described as
Slightly basic
Neutralization reactions are a type of
Double displacement reactions
A solution with a ph of 2 is said to be
Strongly acidic
Catalysts
Speed of rate of reaction
Examples of acids
Battery acid, stomach acid, lemon juice
Examples of bases
Javex, rain water
What’s so unique about a polyatomic ion
They are packages
Difference between poly atomic, ionic, and molecular compounds
Molecular: nonmetal and a nonmetal
Ionic: metal and a nonmetal
Poly atomic: element and a package or a package and a package
Surface area
Increased surface area, means increased rate of reaction
Temperature
Increased temperature means increased rate of reaction
Concentration
Increased concentration means increased rate of reaction
