Chemistry test help

balanced symbol equation

An equation written in such a way that the number of each type of atom is equal on both sides.

Chemical Equation

A balanced symbol equation representing a chemical reaction

Conservation of mass

A law which states that matter is neither created or destroyed in chemical reactions

Formula

The number and type of atoms present present in a single particle of a substance

Metal oxide

A compound formed by combining a metal element with oxygen

Nonmetal oxide

A compound form from combining a non-metal element with oxygen

Oxidation reaction

A reaction in which a substance gained oxygen

Precipitation reaction

A reaction involving the formation of a solid when two solutions are mixed

Thermal decomposition

A reaction which a compound breaks down into two or more substances by the action of heat

thermally stable

Substance is what you’re not chemically change when heated within reason

Word equation

An equation with the reactants of products written as the chemical names

And a simple roles needed to name compounds given their constituent elements or formula

Name the metal first

Then named the non-metal

Use prefixes only when both element elements or nonmetals use Roman numerals when metals have more than one charge

Oxygen change is always negative 2

For CO2 H2O, CH4, CO, and SO2 be able to write formula given their names or names from their formula

CO2 is carbon dioxide

H2O is water

CH4 is methane

CO is carbon monoxide

SO2 is sulphur dioxide

Convert details of chemical reactions written in prose to word equation

E.g carbon dioxide reacts with water to form carbonic acid

Carbon + water —> carbonic acid

Know the general word equation for the reaction of metal of oxygen and be able to construct word equations for specific example know reactions in which oxygen added to another reactant are called oxidation reactions

Metal + oxgyen —> metal oxide

Magnesium + oxygen —> magnesium oxide

Explain mass changes upon heating

Mass changes when heating depending on gases: it increases if oxygen is gained (oxidation), decreases if a gas escapes, and stays the same in a closed system because mass is conserved.

Understand the in chemical reaction the overall mass does not change hence chemical equations using formula must be balanced

Back:
In a chemical reaction, mass is conserved, meaning no atoms are created or destroyed. The same number of each type of atom must be present on both sides of the equation, so chemical equations using formulae must be balanced by adjusting coefficients.

Be abe to balance chemical equitations

Back:
To balance a chemical equation, make sure there are the same number of each type of atom on both sides. You can only change the numbers in front of the formulas (not the formulas themselves). Keep adjusting until both sides match.

Acid

The solutions turn universal indicators red or orange and turns red. They often are corrosive. On the pH scale: strong acid zero, one, two. Weak acids three, four, five, six.

Acidic solution

A solution with a pH less than seven

Alkali

A water soluble base. Makes indicators change colour blue. On the pH scale: weak alkalis, 8,9,10,11 strong alkali 12, 13, 14

Alkaline solution

A solution of a pH of greater than seven

Base

A substance that reacts with an acid to produce a salt and water. Common examples include metal oxide, metal hydroxide and carbonate.

Litmus

An indicator which turned red when put an acid and blue when put in alkali

Methyll orange

An indicator which turned red and put an acid and yellow when put in alkalise

Neutral

A solution that measures seven on the pH scale like water

Neutral solution

A solution for pH of seven at room temperature

Neutralisation

A chemical reaction in which an acid and alkali interact with the formation of a salt

PH scale

a range of numbers commonly running from 0 to 14 that describe the degree of acidity or alkalinity of a solution

Phenolphthalein

An indicator which turned colour less when put an acid and turns Ceris when put in alkali

Salt

A substance in which the hydrogen part of an acid is replaced with metal common example examples includes nitrate chloride and sulphate

Universal indicator

An indicator which can exhibit a range of colours depending on the pH of a solution

The test and positive result for carbon dioxide

Bubbling the gas through lime water is the test and a positive result is when the lime water turns cloudy

Bond breaking

An endothermic process that involves overcoming sources of attraction between particles

Bond making

An exothermic process that gives our energy to the surrounding as new bonds form between particles

Combustion

A process in which a substance reacts to with an oxygen to burn

Complete combustion

A reaction which the constituent elements of a compound react with as much oxygen as possible for this to have an oxygen must be freely available

Cooling curve

A graph shown in a relationship between temperature and time is substance is cooled

Endothermic

A changing in which energy is taken in from the surroundings often resulting in a decrease and temperature

Exothermic

A change of energy is given out to the surroundings often resulting in an increase in temperature

Fire triangle

A representation of the three things required to sustain a fire heat oxygen and fuel

Fuel

A substance which releases energy often in form of heat and light went burnt

Incomplete combustion

Combustion that occurs in a limited supply box and can result in the formation of harmful products such as carbon monoxide

Need a relative proportions of gases and dry air

Nitrogen (n2) 78.08%

Oxygen (02) 20.95%

Argon (ar) 0.93%

Carbon dioxide (co2) 0.04

Positive test result for oxygen

Putting a blowing splint inside magnesium peroxide and if oxygen is present then the splint should re light