SUBSTANCESSubstances are a certain matter that has properties that are uniform with each other, either physically or atomically. Substances may be elements or compounds. Elements, in substances, are those which cannot be broken down or is the most basic form of a substance. Compounds, in substance, are those which can further be broken down. Here are some facts involving substances.
Find out if salt is an element, a compound, or a mixture from this link: brainly.ph/question/2895859 #BrainlyEveryday An element is a substance that cannot be broken down into a simpler format. They are distinguished by a unique atomic number. The elements are organized by their atomic number in the periodic table, which highlights elements with similar properties. Water is an example of a compound, a mixture of two or more elements, and is created when two hydrogen atoms bond to an oxygen atom. Use these resources to examine the properties and uses of elements and compounds. Elements, Compounds, and Mixtures Elements Any substance that contains only one kind of an atom is known as an element. Because atoms cannot be created or destroyed in a chemical reaction, elements such as phosphorus (P4) or sulfur (S8) cannot be broken down into simpler substances by these reactions. Example: Water decomposes into a mixture of hydrogen and oxygen when an electric current is passed through the liquid. Hydrogen and oxygen, on the other hand, cannot be decomposed into simpler substances. They are therefore the elementary, or simplest, chemical substances - elements. Each element is represented by a unique symbol. The notation for each element can be found on the periodic table of elements. The elements can be divided into three categories that have characteristic properties: metals, nonmetals, and semimetals. Most elements are metals, which are found on the left and toward the bottom of the periodic table. A handful of nonmetals are clustered in the upper right corner of the periodic table. The semimetals can be found along the dividing line between the metals and the nonmetals.  Atoms Elements are made up of atoms, the smallest particle that has any of the properties of the element.John Dalton, in 1803, proposed a modern theory of the atom based on the following assumptions.
Compounds Elements combine to form chemical compounds that are often divided into two categories. Metals often react with nonmetals to form ionic compounds. These compounds are composed of positive and negative ions formed by adding or subtracting electrons from neutral atoms and molecules. Nonmetals combine with each other to form covalent compounds, which exist as neutral molecules. The shorthand notation for a compound describes the number of atoms of each element, which is indicated by a subscript written after the symbol for the element. By convention, no subscript is written when a molecule contains only one atom of an element. Thus, water is H2O and carbon dioxide is CO2. Characteristics of Ionic and Covalent Compounds
Determining if a Compound is Ionic or Covalent Calculate the difference between the electronegativities of two elements in a compound and the average of their electronegativites, and find the intersection of these values on the figure shown below to help determine if the compound is ionic or covalent, or metallic. Practice Problem 1: For each of the following compounds, predict whether you would expect it to be ionic or covalent. (a) chromium(III) oxide, Cr2O3 (b) carbon tetrachloride, CCl4 (c) methanol, CH3OH (d) strontium fluoride, SrF2 Click here to check your answer to Practice Problem 1 Practice Problem 2: Use the following data to propose a way of distinguishing between ionic and covalent compounds.
Click here to check your answer to Practice Problem 2 Formulas A molecule is the smallest particle that has any of the properties of a compound. The formula for a molecule must be neutral. When writing the formula for an ionic compound, the charges on the ions must balance, the number of postive charges must equal the number of negative charges. Examples:
Mixtures Vs. Compounds The law of constant composition states that the ratio by mass of the elements in a chemical compound is always the same, regardless of the source of the compound. The law of constant composition can be used to distinguish between compounds and mixtures of elements: Compounds have a constant composition; mixtures do not. Water is always 88.8% O and 11.2% H by weight regardless of its source. Brass is an example of a mixture of two elements: copper and zinc. It can contain as little as 10%, or as much as 45%, zinc. Another difference between compounds and mixtures of elements is the ease with which the elements can be separated. Mixtures, such as the atmosphere, contain two or more substances that are relatively easy to separate. The individual components of a mixture can be physically separated from each other. Chemical compounds are very different from mixtures: The elements in a chemical compound can only be separated by destroying the compound. Some of the differences between chemical compounds and mixtures of elements are illustrated by the following example using raisin bran and "Crispix.". Raisin bran has the following characteristic properties of a mixture.
Crispix has some of the characteristic properties of a compound.
What is true about an element?Elements are substances which consist of only one kind of atoms which cannot be broken down into simpler substances by either physical or chemical processes. They are classified as metals, non-metals and metalloids.
What do elements and compound have in common?Both the element and the compound are pure forms of matter. We can't break an element down any farther into simplest compounds because they're all made out of identical atoms. The composition of both elements and compounds is uniform throughout.
What's true about compounds?Two things are true of all compounds: A compound always has the same elements in the same proportions. For example, carbon dioxide always has two atoms of oxygen for each atom of carbon, and water always has two atoms of hydrogen for each atom of oxygen. A compound always has the same composition throughout.
What is element and compound answer?Element is a pure substance made up of only one kind of atom which can't be split up into two or more substance. compound is a pure substance made up of two or more substance combined in fixed proportion by mass.
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What is true about element and compounds?
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