States of matter
What state of matter takes the shape of its container but has a fixed volume?
Liquid
This element's symbol is 'O' and is essential for respiration in most living organisms.
Oxygen
When does a chemical change occur ?
When the matter changes into a new substance and has a new chemical property.
What is an endothermic reaction?
A reaction that absorbs heat from its surroundings, resulting in a temperature decrease.
What is an exothermic reaction?
A reaction that releases heat to its surroundings, resulting in a temperature increase.
What is a Solid?
This state of matter has a definite shape and volume.
What is the atomic number of hydrogen?
Describe a chemical change that occurs in the human body.
Digestion of food, where complex molecules are broken down into simpler ones, releasing energy and nutrients.
Name a common endothermic reaction that occurs in everyday life.
Melting Ice
Name a common exothermic reaction that occurs in everyday life.
Combustion, such as burning wood or fossil fuels.
What term describes the transition from liquid to solid?
Freezing.
What is the lightest noble gas?
Helium.
How do you know when something has undergone in a chemical change?
Change in Color
Change in Oder
Foundation of Gas
Why do endothermic reactions feel cold to the touch?
Because they absorb heat from their surroundings.
Why do exothermic reactions feel warm to the touch?
Because they release heat to their surroundings.
What is sublimation?
The term for the transition from a solid state directly to a gas, bypassing the liquid state.
Name the element with the highest atomic number that occurs naturally
Uranium (atomic number 92).
What happens to the chemical bonds during a chemical change?
Chemical bonds are broken and new bonds are formed, resulting in new substances.
How can you identify an endothermic reaction in a laboratory setting?
By measuring the temperature drop of the surroundings
How can you identify an exothermic reaction in a laboratory setting?
By measuring the temperature increase of the surroundings or using a calorimeter.
What is plasma?
This state of matter has neither a definite shape nor a definite volume and is made up of ionized particles.
What element is commonly known as the 'king of chemicals'?
Sulfuric acid (due to its widespread industrial use).
What is the difference between a chemical change and a physical change?
A chemical change produces new substances, while a physical change affects the form or appearance of a substance without changing its chemical identity.
What is the difference between an endothermic reaction and an exothermic reaction?
Endothermic reactions absorb heat, while exothermic reactions release heat.
In what phase change is heat released by a substance without lowering its temperature?
During the phase change from liquid to solid (freezing) or gas to liquid (condensation).