Energy is the ability to do work. What must occur in a substance in order to determine a chemical property? A chemical property can be determined only
when a change in the substance occurs in the presence of another substance
or when sufficient energy of some form is added to it.
How do you determine the chemical properties of a substance?
The chemical properties of a substance can be determined by
performing experiments that use specific materials or processes with known characteristics
. If a material affects the substance in a given way, the substance has a particular property. If a process changes the substance, more properties can be deduced.
What are chemical properties of substances?
What is a chemical property? A chemical property is
a characteristic of a particular substance that can be observed in a chemical reaction
. Some major chemical properties include flammability, toxicity, heat of combustion, pH value, rate of radioactive decay, and chemical stability.
Why do we have to determine the chemical properties of materials?
Chemical properties are of great interest to materials science. These characteristics help scientists classify samples,
identify unknown materials
, and purify substances. Knowing the properties helps chemists make predictions about the type of reactions to expect.
What are the 5 chemical properties?
Examples of chemical properties include
flammability, toxicity, acidity, reactivity (many types)
, and heat of combustion.
How might you go about testing an unknown substance to determine its chemical properties?
Melting and boiling points
: Most chemicals have melting and boiling points that are very different from others. If you can accurately find the melting and/or boiling temperature of your unknown chemical, you can probably match that value to a table of melting and boiling points to identify your unknown.
Which of the following indicates a chemical property?
The change of one type of matter into another type (or the inability to change) is a chemical property. Examples of chemical properties include
flammability, toxicity, acidity, reactivity (many types)
, and heat of combustion.
How are physical and chemical properties used to identify substances?
Characteristics such as melting point, boiling point, density, solubility, color, odor, etc. are physical properties. Properties that describe how a substance
changes
identity to produce a new substance are chemical properties. … Physical and chemical properties can be used to classify a substance as ionic or molecular.
What properties of a substance determine how that substance will react when combined with other substances?
Chemical properties describe the characteristic ability of a substance to react to form new substances; they include its
flammability and susceptibility to corrosion
. All samples of a pure substance have the same chemical and physical properties.
Why it is important to know the chemical properties of substances before you work with them in the laboratory?
As a responsible scientist, you should understand these four properties for every chemical that you use in the lab and in your experiment. … The MSDS
describes the properties and potential hazards of the material
, how to use it safely, how to dispose of it safely when you are done, and what to do in an emergency.
Which of the following is used to determine an unknown substance?
You can identify an unknown substance by
measuring its density and comparing your result to
a list of known densities. Density = mass/volume. Assume that you have to identify an unknown metal. You can determine the mass of the metal on a scale.
What test can we perform to identify an unknown substance?
Simple chemical tests can be used to identify the presence of various elements or classes of molecules (Tollen’s test).
Gravimetric analysis
: You use the change in mass during an experiment to figure out what you’ve got.
How do you determine the identity of an unknown substance?
Scientists already have determined the densities of many substances. As a result, you can conveniently compare the density of an unknown substance with the densities of known substances.
Finding any matching densities
will give you information about the possible identity of the unknown substance.
Which of the following indicates that a chemical reaction has occurred?
Some signs of a chemical change are a
change in color and the formation of bubbles
. The five conditions of chemical change: color change, formation of a precipitate, formation of a gas, odor change, temperature change.
Which characteristic is not a chemical property?
Melting point
is not a chemical property.
What must occur for a change to be a chemical reaction?
A chemical change must occur.
You start with one molecule and turn it into another
. Chemical bonds are made or broken in order to create a new molecule. One example of a chemical reaction is the rusting of a steel garbage can.
What factors determine the physical properties of a substance?
- The kinetic energies of the particles (atoms, molecules, or ions) that make up a substance. Kinetic energy tends to keep the particles moving apart.
- The attractive intermolecular forces between particles that tend to draw the particles together.
Does observing a physical property of a substance change the identity of the substance?
A physical property can always be observed without changing the identity of a substance
. A chemical property, however, is observed by attempting to change the identity of a substance.
What characteristics distinguish a mixture from a substance?
Mixtures are
physically combined structures that can be separated into their original components
. A chemical substance is composed of one type of atom or molecule. A mixture is composed of different types of atoms or molecules that are not chemically bonded.
What are the 3 properties of matter?
The three basic properties of matter are
volume, mass, and shape
. 2. All matter is made up of tiny particles called atoms.
How do you identify physical properties?
Physical properties are those general properties you notice most readily about a substance, such as its size, state of matter (solid, liquid, or gas), color, mass, density and strength. Values for physical properties can be
determined by tests that don’t alter the substance being tested
.
What steps do you suggest to ensure information security in your laboratory?
- Lock doors when not occupied.
- Make sure all laboratory personnel receive security awareness training.
- Control access to keys and use judgment in providing keys to visitors.
What is the first step in identifying a chemical?
What is the first step in identifying a chemical? AnswerThe first step in identifying a chemical is
to check all the physical properties like
…
How do you determine what a substance is?
- chemical name, for example, benzene;
- number, for example, EC number 200-753-7, and.
- chemical composition, for example, >99 % benzene and <1 % toluene. The composition is determined by chemical analysis.
What is the substances are identified in different phases?
The three fundamental phases of matter are
solid, liquid, and gas (vapour)
, but others are considered to exist, including crystalline, colloid, glassy, amorphous, and plasma phases. When a phase in one form is altered to another form, a phase change is said to have occurred.
What must occur in order for a chemical reaction to be specifically classified as endothermic?
What must occur in order for a chemical reaction to be specifically classified as endothermic instead of exothermic?
Energy is absorbed in the form of heat
. … What is known about an endothermic reaction? The new substance will need more energy to form its chemical bonds than the old substance will release.
What is a starting substance in a chemical reaction?
These starting substances of a chemical reaction are called
the reactants
, and the new substances that result are called the products. … between reactants and products.
In which steps did a chemical change occur?
Chemical changes occur
when bonds are broken and/or formed between molecules or atoms
. This means that one substance with a certain set of properties (such as melting point, color, taste, etc) is turned into a different substance with different properties.
