Chemical Change Flashcards
What is chemical change?
Chemical change is a change that makes a new chemical. It is irreversible. Like burning paper.
What is physical change?
A physical change is a change in the appreance of a substance. A physical change is still the same but has a different appearance. Physical changes are usually reversible. Examples include melting ice.
What is a chemical reaction?
A chemical reaction can also be described as chemical change. In chemical changes or reactions chemical substances change to create new substances.
How do you write chemical reactions?
A + B ➡️ C + D
This means the reactants A and B chemically react to form reactants C and D.
Are these physical or chemical change;
Melting ice, freezing, tearing paper, breaking, candles melting and inflating a balloon.
Physical change
Are these chemical or physical change?
Fire crackers bursting, rotting fruit, cooking sugar, frying chips, burning matches, rusting iron and roasting.
Chemical change
List the characteristics of physical change?
Shape or phase may change, no new substance is produced, a change from one state to another without changing chemical composition.
List the characteristics of chemical change?
All substances have changed, new substances are formed, changes happen at molecule level, the breaking and goring of chemical bonds.
How you determine whether the change is physical or chemical?
You can determine whether the change is physical or chemical due to the difference in size, colour change, solid formation and heat given off.
What is a product?
A substance which is formed as the result of chemical change.
What is the PH scale?
A measure of alkalinity or acidity of water soluble subtances. (Things that dissolve in water). PH stands for Potential of Hydrogen.
What is a reactant?
Substances initially present in chemical reaction that are consumed during the reaction to make products.
What is salt? (Not the food)
In chemistry, a salt is an ionic compound that results from the neutralisation reaction of acid and base. Salts are composed of related numbers of cations and anions so that the product is electrically neutral.
What is an exothermic reaction?
An exothermic reaction is a reaction that will release energy into its environment.
What is an endothermic reaction?
An endothermic reaction is a reaction that will take energy from the environment.
