thermal energy changes

Thermal energy changes

​lesson 3 revision

by huda wasim

​thermal energy

• Energy: energy is the ability to do work

• ​temperature: the measure of motion and energy of the particles

• ​thermal energy : total kinetic and potential energy of particles.

• energy which flows from warm to cold places

​exo and endo thermic

• ​when matter changes energy is absorbed-endothermic

• ​energy is released-exothermic

• ​Melting of ice -endo

• ​combustion burning-exo

• ​chemical energy is stored in the bonds

Multiple Choice

The motion of atoms or molecules within a substance

• temperature

• thermal energy

• kinetic energy

• solid

Multiple Choice

The average kinetic energy of the atomes or molecules within a substance.

• thermal energy

• kinetic energy

• temperature

• gas

Multiple Choice

A process that creates new substances from existing substances and can absorb or release thermal energy

• chemical reaction

• thermal energy

• temperature

• kinetic energy

Multiple Choice

Which is an example of an endothermic reaction?

• a candle burning

• iron rusting

• a silver spoon tarnishing

• an ice cube melting

Multiple Choice

What is the ability to do work or cause change?

• temperature

• energy

• thermal energy

• exothermic

Multiple Choice

This is a change in energy that is taken in.

• endothermic

• thermal energy

• exothermic

• physical change

​Law of conservation of mass

​Mass is neither created nor destroyed it stays the same before and after a chemical reaction

​

​Mass is not lost or gained

Multiple Choice

What will weigh more when a chemical change is complete?  The reactants before the chemical reaction, or the product after the reaction is complete?

• They both will weigh the same
• The product always weighs more than the reactant
• The reactant will weigh more than the product
• They both will loose mass after the reaction

Multiple Choice

According to the Law of Conservation of Mass, what happens to the wood and oxygen when it is burned?

• The wood disappears.

• It stays the same chemically.

• The atoms in the wood and oxygen rearrange and form smoke and ash.

• Nothing.

Multiple Choice

The law of conservation of mass states that ________

• the total mass of reactants is more than the total mass of products

• the mass of a chemical reaction is not constant

• the mass of a chemical reaction remains constant

• the total mass of reactants is less than the total mass of products

​Changes

• ​physical change: on form or shape changes

• ​chemical change: A chemical reaction happens, a new substance is formed

Multiple Choice

Which of the following is NOT an example of a physical change?

• crumpled paper
• pencil sharpening
• shrunken clothing
• rust

Multiple Choice

A change where one or more new substances are created.

• Physical Change 
• Chemical Change 

Multiple Choice

Fizzing, foaming, and burning are all examples of

• Chemical change
• Physical change

Multiple Choice

Water freezing

• Chemical Change
• Physical Change