There are a few telltale signs that can help indicate that a chemical reaction has taken place; these include the creation of one or more new substances and a noticeable energy change from the reaction site. However, telling whether a chemical reaction has actually taken place is not always very easy to observe.Know More
These changes can be noted in two different ways, through appearance changes and energy changes.
It is important to note that these signs are merely indicators, not proof, that a reaction has taken place and that the only true sign that a chemical reaction has occurred is the creation of one or more substances as a result of the chemical interaction.Learn more about Chemistry
Lemonade is a mixture because sugar, water and lemons are combined together without a chemical reaction taking place. The bonds of the substances can't combine with one another, instead the three items are mixed up.Full Answer >
When sugar is burned, chemical changes take place, depending on if the sugar is burned in a complete or an incomplete combustion reaction. During a complete combustion reaction, sugar is transformed into CO2 and H20. In an incomplete combustion reaction that uses lower heat, ring polymerization and charring may occur.Full Answer >
The effect of a catalyst on a chemical reaction is to increase the rate of that reaction by reducing its activation energy. This activation energy is the energy required to move chemical reactants into a transition state, which is intermediate between reactant and product.Full Answer >
Energy can play many different roles in chemical reactions, and it can be a product of a chemical reaction, a necessary component for a chemical reaction, or energy can have little part in a chemical reaction. Chemical reactions that require additional energy are called endothermic reactions, while those that produce energy are called exothermic reactions.Full Answer >