Structure and Properties of Matter Test Review Sheet (6th Grade) Chemical properties include oxidation, flammability, and combustibility. Density is an example of a physical property. Mass is an example of a physical property. The temperature at which a liquid becomes a gas is the boiling point. Density depends on mass and volume (d = m / v). Melting points are physical properties. You can separate sugar from sand because sugar is soluble in water and sand is not. A bonfire is an example of the property of combustibility. The ability to react with oxygen is an example of a chemical property. Reactions with oxygen are examples of chemical properties. Physical changes include freezing, dissolving, and evaporating (substance does not change chemically). Burning is an example of a chemical change (substance does change chemically). Example: burning wood produces ash (carbon), a different substance. Fruit rotting or changing color indicates that a chemical change has taken place. Frying a hamburger is an example of a chemical change. The mass of the products of a chemical reaction is the same as the mass of the reactants. A substance is matter that has the same composition and properties throughout. When two pure substances are combined so that each of the pure substances retains its own properties, the result is a mixture. Example: salt water is a mixture of salt and water. All metals are solids at room temperature except for mercury. To determine how many atoms of an element are in a compound, look at the small number (subscript) to the right of the element. Metals are mostly good conductors of electricity, malleable and ductile, and good conductors of heat. Nonmetals are mostly gases at room temperature. For the most part, nonmetals are poor conductors of heat, are brittle, and are poor conductors of electricity. Metals, however, are good conductors of heat. Water (H20) and hydrogen peroxide (H2O2) have different properties because they contain different percentages of oxygen. Matter has mass and takes up space, can be divided into pure substances and mixtures, and is made up of atoms. Most of the mass of an atom is found in its nucleus. Vegetable soup is an example of a heterogeneous mixture. Matter is anything that has mass and takes up space. An example of something that cannot be classified as matter is heat. Air is matter (has mass and takes up space). Additional Information to Study The differences in the energy of particles/molecules in solids, liquids, and gases. Be able to identify chemical or physical changes, along with how to explain the differences between the two.