The Properties Of Matter

The least dense liquid is found floating at the top because density is a measure of how much mass is contained in a given volume. The least dense liquid will have fewer particles packed closely together, resulting in a lighter mass per unit volume. As a result, it will be less dense than the other liquids and will float on top of them.

The volume of a liquid, such as mercury, is best described using units of liters or milliliters. Grams and kilograms are units of mass, not volume. Meters and centimeters are units of length, not volume. Newtons are units of force, not volume. Therefore, the most appropriate units for describing the volume of mercury in an experiment would be liters or milliliters.

Melting candle wax is an example of a physical change because it involves a change in the physical state of the substance without altering its chemical composition. The wax changes from a solid to a liquid when heated, but its molecular structure remains the same. This can be reversed by cooling the liquid wax, demonstrating that no new substances are formed during the process. Therefore, melting candle wax is considered a physical change rather than a chemical change.

Iron rusting is a chemical reaction that occurs when iron reacts with oxygen in the presence of water or moisture. This reaction forms iron oxide, commonly known as rust. Therefore, the chemical property responsible for iron rusting is its reactivity with oxygen.

Density is the physical property of matter that describes the relationship between mass and volume. It is a measure of how much mass is contained within a given volume of a substance. Density is calculated by dividing the mass of an object by its volume. Different substances have different densities, and it can be used to identify and classify materials.

A physical change is different from a chemical change because it is reversible. This means that the original substance can be restored after the change has occurred. In contrast, a chemical change results in the formation of a new substance with different properties, and it is usually not reversible.

Weight is a measure of the gravitational force acting on an object. It is the force with which an object is pulled towards the center of the Earth or any other celestial body. Weight depends on the mass of the object and the acceleration due to gravity. It is different from mass, which is a measure of the amount of matter in an object. Density is the mass of an object divided by its volume, and volume is the amount of space occupied by an object. Therefore, weight is the correct answer as it directly relates to the gravitational force.

The correct answer is "more mass than the 50g ball." Mass is a measure of the amount of matter in an object, and it determines the inertia of the object. Inertia is the resistance of an object to changes in its motion. The ball with a mass of 150g has more matter packed into it compared to the ball with a mass of 50g. Therefore, it would be more difficult to move the ball with more mass because it has more inertia.

Souring milk is an example of a chemical change because it involves a chemical reaction. When milk sours, the lactose in the milk is converted into lactic acid by bacteria. This change in composition and the formation of a new substance (lactic acid) is characteristic of a chemical change.

A change in state is not a sign of a chemical change because it is a physical change. A change in state refers to a substance transitioning from one phase to another, such as from a solid to a liquid or a gas. This change does not involve the alteration of the substance's chemical composition or the formation of new substances. In contrast, the other options mentioned - change in color or odor, foaming or bubbling, and production of heat or light - are all indicators of a chemical change, as they involve the transformation of the substance's chemical properties.

Malleability is the ability of a substance to be deformed or shaped under compression without breaking or cracking. This property is a characteristic of the material itself and does not involve any change in its chemical composition. Therefore, malleability is considered a physical property.