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 in Chemistry
The molecules of one reactant are combined with those of another reactant to form a new substance during a chemical reaction. As the chemical bonds are broken, the positions of electrons change, resulting in a product with properties that are different from the properties of the reactants. Various temperatures and catalysts are needed for different chemical reactions to occur.Full Answer >
The chemical reaction for fermentation is expressed as the chemical equation: C6H12O6 ? 2 C2H5OH + 2 CO2. Showing the alcoholic fermentation of glucose as chemical formula C6H12O6, this one glucose molecule is converted into two ethanol molecules expressed as 2C2H5OH and two carbon dioxide molecules expressed as 2CO2.Full Answer >
A chemical reaction can be shown to be endothermic if it absorbs heat and causes a decrease in the temperature of its surroundings. Illustrative lab experiments performed in schools to demonstrate endothermic reactions often use the reaction occurring between vinegar and baking soda or the reaction between barium hydroxide and ammonium nitrate. The latter reaction, if taking place in a flask resting in a small amount of water, will absorb enough heat from the water to cause it to freeze.Full Answer >
The chemical reaction between aluminum and bromine is an exothermic one that produces aluminum bromide. The equation of the chemical reaction is 2 Al + 3 Br2 ? 2 AlBr3. It indicates that two molecules of aluminum combine with three molecules of bromine to produce two molecules of aluminum bromide.Full Answer >