Physical And Chemical Change Lab

Every individual is different in a specific way. Like people, substances have unique qualities, such as properties, which aid chemists to differentiate and identify the particular components the substances consists of. These particular qualities are identified as either physical or chemical properties. Physical properties are properties which do not require a chemical change of its composition in order for the substance to be classified. A few examples of physical properties include color, density, odor, boiling point, melting

6-3: This process is used by cells to manufacture _biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products__

Procedure: In this experiment, various chemicals were mixed together, to determine a reaction. Using two drops from chemical 1 and two drops of chemical two, unless otherwise stated, then recording the type of physical reaction or color changes that occurred.

A physical change includes a change in the material without affecting its composition, such as the physical state change. However, a chemical change includes the change in the composition of the substance. The change in color, formation of a gas or a solid product, and the production of energy are the evidences of a chemical reaction, thus, of a chemical change.

The purpose of this lab is to test substances and to determine the physical and chemical properties of substances.

The composition of a pure substance is constant, and thus pure substances have characteristic physical properties that do not change and this is why we are able to separate each element in this lab experiment. Examples of physical properties that can be used to describe pure substances include solubility, conductivity, magnetism, density, boiling point, and melting point.

Introduction: Chemical reactions are dependent upon two factors: temperature and concentrations of substance. We can monitor the rate at which a chemical decomposes or the rate at which a chemical substance appears. In this experiment we will be measuring the rate of decomposition of hydrogen dioxide with the following reaction:

In this experiment you will observe some physical and some chemical changes. You will observe that energy must be used to start some chemical reactions, and that it is produced in others.

The proof (twice the % alcohol) starts at its maximum and goes down (as the alcohol evaporates). If we start with a high concentration of alcohol, we will get the azeotrope (95% alcohol, 5% water) for a while, then the concentration will decrease.

The luminous yellow flame is smoky because no air is entering the burner and hydrocarbon is converted into carbon dioxide

Physical changes occurred in four out of the eight experiments completed in this lab. The first was experiment one, the salt and water. The salt was added to water but when the water evaporated the salt remained. The water changed to the vapor form of water and the salt did not change. The second was experiment two, the candle. When the candle was lit the heat given off from the fire melted the wax beneath it. Melting is a physical change because the liquid wax is still wax, its usual form is just a solid. Experiment four dealt with ripping paper. This was a physical change because, although the paper was being ripped apart, it was (and still is) paper. The smaller pieces did not change the mass or any other factor of it except the surface area of each piece. Experiment seven dealt with vinegar being added to milk. The vinegar did not change but the milk was curdled by the vinegar. Although the milk was curdled, the milk remained milk. The composition stayed the same. Each of these experiments showed no change in a substance so as it changed to another substance.

Physical changes can be seen through an altering of the substances physical property. A substances physical property is observed and measured without changing the composition of the subject. Descriptive words that would help to identify a substance’s physical property include hard, soft, brittle, flexible, heavy, and light just to name a few.

The objective of this experiment was to allow one to grasp a thorough understanding of chemical reactions and the way they occur in chemistry. The study of chemical kinetics is known as reaction rates, which occur at different speeds. The speed of chemical reactions are dependent on four factors. The main factors that contribute to altering the speed are: the nature of the reactants, the concentration of the reactants, the presence of a catalysis and lastly, temperature (CHCKY107 General Chemistry Lab Manual Spring 2018). By incrementing the temperature in a chemical reaction, this incrementation in heat will accelerate the process, creating more collision in particles as which because they are more motion, creating an increase in kinetic

Physical properties are observable without changing the identity of the substance. Examples of physical properties would be; size, shape, freezing point, boiling point, melting point, density, etc. Chemical properties aren’t observable without changing the identity of the substance. Examples of chemical properties would be; flammability, creating gas bubbles, creating new chemical product, rusting, etc. In a physical change the identity of the substance doesn’t change. But in a chemical change the identity of the substance does change. In this experiment we observed and created the five scenarios. In scenario one we mixed in five grams of table salt to 100mL of water. In scenario two we heated up a 2cm magnesium strip in a crucible. Then scenario

Physical property: characteristic of a substance that can be observed without altering the identity of the substance