STEMscopedia-Physical & Chemical Changes

Match the description to the vocabulary term. physical property a characteristic that can be observed or measured without changing the substance chemical property a characteristic that can be observed or measured only when atoms rearrange during a chemical change matter anything that has volume and mass physical change a change to a substance that occurs without forming a new substance, such as a change in size or state of matter chemical change a change that involves one substance being pulled apart or combined with another substance to form a completely different substance or substances Read the passage. PHYSICAL CHEMICAL CHANGESChanges happen all around us, and they can be grouped into two types: physical changes and chemical changes. Physical changes are when something changes its appearance or form, but it doesn't become a completely different substance. It's like when you cut a piece of paper into smaller pieces or bend a pipe cleaner. The paper is still paper, and the pipe cleaner is still a pipe cleaner, but they look different. In physical changes, the matter stays the same, but its shape, size, or state might change. Chemical changes, on the other hand, are when a substance changes into something new. Imagine mixing baking soda and vinegar together. They react and create bubbles. This is a chemical change because new substances are formed. Some other examples of chemical changes include rusting metal, burning wood, or baking a cake. In all of these cases, the original substances change and become something different. Sometimes it can be a little tricky to tell the difference between physical and chemical changes. But don't worry, there are clues that can help us figure it out. One clue is if there’s a color change or the production of bubbles, heat, or light. These are often signs of a chemical change. Also, if you can't change the substance back to how it was before, it's likely a chemical change. Which of the following best describes a physical change? Burning a piece of wood Rusting of metal Cutting a piece of paper into smaller pieces Baking a cake What is the main difference between a physical change and a chemical change? Physical changes always produce bubbles, but chemical changes do not Chemical changes create new substances, while physical changes do not Physical changes only happen with solids, while chemical changes happen with liquids Chemical changes can always be reversed, but physical changes cannot Which of the following is an example of a chemical change? Cutting a sheet of aluminum foil Melting ice into water Bending a pipe cleaner Mixing baking soda and vinegar to make bubbles Which clue often tells us that a chemical change has occurred? A change in size A change in color or the production of bubbles A change in shape Breaking something into smaller pieces If a change cannot be reversed, it is most likely a… State of matter change Physical change Size change Chemical change Using your knowledge of Physical Chemical Changes, sort the examples. Physical Changes cutting an object ice cream melting breaking a bone stretching a rubberband water freezing smashing a cake Chemical Changes stomach digesting firework explosion burning wood rusted car baking a cake elephant toothpaste A physical change happens when matter changes in size, shape, or state but stays the same substance.Physical changes are often reversible, meaning they can be undone.Examples of physical changes include crumpling paper or bending a metal wire.A chemical change happens when matter forms a new substance.Chemical changes are usually irreversible, which means they cannot easily be undone.Rust forming on iron or burning wood are examples of chemical changes. Explain in your own words how you can tell the difference between a physical and a chemical change.