Chemical and physical properties and changes! Flashcards
What are the physical properties of a substance?
*Colour
*Solid, liquid, or gas(state of matter)
*Boiling or melting temperature/point
*Heavy or light(weight)
What are the chemical properties of a substance?
*How acidic or alkaline it is
*How it reacts with water, metals, or acids
*How steadily it reacts
What are some physical and chemical properties of iron?
Iron is a grey, heavy solid metal and has a melting point of 1538 degrees Celsius.When iron is heated with sulphur, iron sulfide is formed and when combines with oxygen to form iron oxide or rust.
Physical and chemical properties of hydrochloric acid?
Hydrochloric acid is a colourless liquid with a pH of 2.
What happens in a physical change?
In a physical change, no new substances are formed. For example, when water freezes, it changes state but it is still the same substance.
What happens in a chemical change?
In a chemical change, new substances are formed. For example, when iron and sulphur are heated together, they form a new substance, which is a compound called iron sulfide.
What happens in a chemical reaction?
In a chemical reaction, new products are formed from the reactants.
What is one of the most useful clues to help decide if a chemical reaction has taken place?
One of the most useful clues to help decide if a chemical reaction has taken place is whether a gas is given off.
Which gas is given off when magnesium reacts with hydrochloric acid?
Hydrogen gas
Which gas is given off when baking soda and vinegar react?
Carbon dioxide gas
How to test for carbon dioxide?
You can test for carbon dioxide by using limewater. When limewater is mixed with carbon dioxide, the limewater turns cloudy.
When a piece of apple is placed in hydrogen peroxide, which gas is given off?
Oxygen gas
How to test for oxygen?
To test for oxygen, you use a glowing splint. When a glowing splint is placed in the mouth of a test tube, it will relight if the gas is oxygen.
What does cloudy mean?
Cloudy means that the limewater becomes opaque(from clear), forming a milky white precipitate.
What does glowing mean?
Glowing means that it’s burning with a faint flame, due to combustion
What does pop mean?
Pop refers to a sudden, squeaky sound that is made when a lighted splint is placed in hydrogen gas
