Chemical Reactions

Litmus paper changes

________ colour depending on whether something is an acid or alkali.

Combustion

________ is good as it gives off energy in the form of light and heat.

Hydrogen

A Hydrocarbon is just ________ and Carbon together (CH4)

Oxidation

________ is when a substance reacts and combines with oxygen.

mass

No ________ is lost or gained in a chemical reaction as no particles are added or removed.

Atoms

________ are not created nor destroyed in a chemical reaction and all the ________ in the reactants are in the products, however, they are rearranged.

sodium

There are many different types of salts, such as ________ chloride (table salt), copper sulfate, ________ nitrate and more.

Acids

________ can burn through the skin.

Handwarmers

________ are exothermic.

Rainwater

________ is acidic due to pollution, and acid rain, which is just extremely polluted rain, has more acid.

Thermal Decomposition

________ is the breaking down of a singular substance into two or more different substances.

Visible changes

________ also occur in a chemical reaction.

Chemical reactions

________ are always balanced, however, you need to figure out how to balance them on paper.

Exothermic reaction

In a(n) ________, heat energy is given out.

Warm colours

________ are acids and cool colours are alkalis.

Catalysts

________ increase the speed of a chemical reaction and they are not changed nor used up themselves and are reusable.

universal indicator

The ________ shows whether something is an acid or alkali and also shows the pH number which indicates how strong it is.

symbol equation

A(n) ________ shows the chemical symbols and how many of each molecule or atom there is.

combustion

There are three things necessary for ________, which is burning using oxygen.

Oxidation

________ is another form of a chemical reaction.

Catalysts

________ help industries as they increase the speed of the reaction, lower the temperature needed, make reactions cheaper and they increase the number of products made in a given amount of time, however, they are expensive to buy and different reactions need different catalysts, and they can be poisoned and required to be cleaned.

Chemical reactions

________ do involve a change in energy, such as taking in or giving out different energies, such as heat, light or sound.

exothermic reactions

In addition, condensing and freezing are ________, as they are giving out their energy to be able to cool and then condense /freeze.

Catalysts

________ also decrease the minimum amount of energy required to start a reaction and lower the temperature needed to start the reaction.