What are word equations

In chemistry, a word equation is a chemical reaction expressed in words rather than chemical formulas. A word equation should state the reactants (starting materials), products (ending materials), and direction of the reaction in a form that could be used to write a chemical equation.

There are some key words to watch for when reading or writing a word equation. The words «and» or «plus» mean one chemical and another are both reactants or products. The phrase «is reacted with» indicates the chemicals are reactants. If you say «forms», «makes», or «yields», it means the following substances are products.

When you write a chemical equation from a word equation, the reactants always go on the lefthand side of the equation, while the reactants are on the righthand side. This is true even if the products are listed before the reactants in the word equation.

Word Equation Examples

The chemical reaction 2 H₂(g) + O₂(g) → 2 H₂O(g) would be expressed as:

hydrogen gas + oxygen gas → steam
As a word equation or as «Hydrogen and oxygen react to form water» or «Water is made by reacting hydrogen and oxygen.»

While a word equation doesn’t ordinarily include numbers or symbols (Example: You wouldn’t say «Two H two and one O two makes two H two O», sometimes it is necessary to use a number to indicate the oxidation state of a reactant so that a person writing a chemical equation can do it correctly. This is mostly for the transition metals, which can have multiple oxidation states.

For example, in the reaction between copper and oxygen to form copper oxide, the chemical formula of copper oxide and the number of copper and oxygen atoms involved depends on whether copper(I) or copper(II) participates in the reaction. In this case, it would be fine to say:

copper + oxygen → copper(II) oxide

or

Copper reacts with oxygen to produce copper two oxide.

The (unbalanced) chemical equation for the reaction would start out as:

Cu + O₂ → CuO

Balancing the the equation yields:

2Cu + O₂ → 2CuO

You would get a different equation and product formula using copper(I):

Cu + O₂ → Cu₂O

4Cu + O₂ → 2Cu₂O

More examples of word reactions include:

• Chlorine gas reacts with methane and carbon tetrachloride to produce hydrogen chloride.
• Adding sodium oxide to water produces sodium hydroxide.
• Iodine crystals and chlorine gas react to make solid iron and carbon dioxide gas.
• Zinc and lead two nitrate make zinc nitrate and lead metal.
  which means: Zn + Pb (NO₃)₂ → Zn(NO₃)₂ + Pb

Why Use Word Equations?

When you’re learning general chemistry, work equations are used to help introduce the concepts of reactants, products, the direction of reactions, and to help you understand precision of language. They may seem annoying, but are a good introduction to the thought processes required for chemistry courses. In any chemical reaction, you need to be able to identify the chemical species that react with each other and what they make.

Word Equations in Other Sciences

Chemistry isn’t the only science to use equations. Physics equations and mathematical equations may also be expressed in words. Usually in these equations two statements are set to be equal to each other. For example, if you way «force equals mass multiplied by acceleration» then you are providing the word equation for the formula F = m*a. Other times, one side of the equation may be less than (<), greater than (>), less than or equal to, or greater than or equal to the other side of the equation. Addition, subtraction, multiplication, division, logs, square roots, integrals, and other operations can be stated in word equations. However, complex equations that contain parentheses to describe the order of operations are very hard to understand as word equations.

Source

• Brady, James E.; Senese, Frederick; Jespersen, Neil D. (December 14, 2007). Chemistry: Matter and Its Changes. John Wiley & Sons. ISBN 9780470120941.

D. Updated October 07, 2019. In chemistry, a word equation is a chemical reaction expressed in words rather than chemical formulas. A word equation should state the reactants (starting materials), products (ending materials), and direction of the reaction in a form that could be used to write a chemical equation.

How do you write chemical reaction equations?

Writing Chemical Equations

1. In a chemical equation, the reactants are written on the left, and the products are written on the right.
2. The coefficients next to the symbols of entities indicate the number of moles of a substance produced or used in the chemical reaction.

What is the chemical equation for carbon dioxide?

CO2

What is the formula of carbon dioxide water and oxygen?

Carbon monoxide reacts with oxygen to produce carbon dioxide. Write the balanced chemical equation for this reaction….Example.

In algebra, an equation can be defined as a mathematical statement consisting of an equal symbol between two algebraic expressions that have the same value. For instance, 3x + 5 = 14 is an equation, in which 3x + 5 and 14 are two expressions separated by an ‘equal’ sign.

What must an equation have?

An equation is written as two expressions, connected by an equals sign (“=”). The expressions on the two sides of the equals sign are called the “left-hand side” and “right-hand side” of the equation. An equation is analogous to a scale into which weights are placed.

How do you write in slope intercept form?

Slope-intercept form, y=mx+b, of linear equations, emphasizes the slope and the y-intercept of the line. Watch this video to learn more about it and see some examples.

How do you write an equation for slope?

The slope-intercept form is written as y = mx+b, where m is the slope and b is the y-intercept (the point where the line crosses the y-axis). It’s usually easy to graph a line using y=mx+b. Other forms of linear equations are the standard form and the point-slope form.

What is the equation of the straight line?

The general equation of a straight line is y = mx + c, where m is the gradient, and y = c is the value where the line cuts the y-axis. This number c is called the intercept on the y-axis.

How do you graph a line from an equation?

To graph the equation of a line written in slope-intercept (y=mx+b) form, start by plotting the y-intercept, which is the b value. The y-intercept is where the line will cross the y-axis, so count up or down on the y-axis the number of units indicated by the b value.

How do you plot a line?

To create a line plot, ​first create a number line that includes all the values in the data set. Next, place an X (or dot) above each data value on the number line. If a value occurs more than once in a data set, place ​an Xs​ over that number for each time it occurs.

What are three methods used to graph a linear equation?

There are three basic methods of graphing linear functions. The first is by plotting points and then drawing a line through the points. The second is by using the y-intercept and slope. The third is applying transformations to the identity function f(x)=x f ( x ) = x .

How do you write system of equations?

Writing Systems of Equations: Step 1: Define the variables. Step 2: Write 2 equations from the phrases. Step 3: Use substitution, elimination, or graphing to solve for variables. Step 4: Answer question using proper units.

How do you do system of equations?

Here’s how it goes:

1. Step 1: Solve one of the equations for one of the variables. Let’s solve the first equation for y:
2. Step 2: Substitute that equation into the other equation, and solve for x.
3. Step 3: Substitute x = 4 x = 4 x=4 into one of the original equations, and solve for y.

What are the 3 methods for solving systems of equations?

There are three ways to solve systems of linear equations: substitution, elimination, and graphing. Let’s review the steps for each method.

What is the easiest way to solve system of equations?

The three methods most commonly used to solve systems of equation are substitution, elimination and augmented matrices. Substitution and elimination are simple methods that can effectively solve most systems of two equations in a few straightforward steps.

How do you solve a system of equations with 3 variables?

Pick any two pairs of equations from the system. Eliminate the same variable from each pair using the Addition/Subtraction method. Solve the system of the two new equations using the Addition/Subtraction method. Substitute the solution back into one of the original equations and solve for the third variable.

In chemistry, a word equation is a chemical reaction expressed in words rather than chemical formulas. The words “and” or “plus” mean one chemical and another are both reactants or products. The phrase “is reacted with” indicates the chemicals are reactants.

How do you write equations in Word 2016?

Write an equation or formula

1. Choose Insert > Equation and choose the equation you want from the gallery.
2. After you insert the equation the Equation Tools Design tab opens with symbols and structures that can be added to your equation.

How do you insert equations in Word Mobile?

Write equations

1. Open your Word document.
2. Tap Home and select Insert.
3. Under Insert, choose Insert New Equation. You get the prompt to type a new equation.
4. After you type your equation in linear format, tap to see Math Options.
5. Choose Professional to have your equations appear as display format.

Can you do AutoSum in Word?

You don’t need Excel to calculate values in Word. Just drop your values into a table, insert the right formulas, and you’re done! Simply click in a cell to the right or below a contiguous row or column and click the AutoSum button on the Tables And Borders toolbar. …

What are the shortcut keys for autosum?

The Autosum Excel shortcut is very simple – just type two keys:

• ALT =
• Step 1: place the cursor below the column of numbers you want to sum (or to the left of the row of numbers you want to sum).
• Step 2: hold down the Alt key and then press the equals = sign while still holding Alt.
• Step 3: press Enter.

How do you sum a column?

On your Android tablet or Android phone

1. In a worksheet, tap the first empty cell after a range of cells that has numbers, or tap and drag to select the range of cells you want to calculate.
2. Tap AutoSum.
3. Tap Sum.
4. Tap the check mark. You’re done!

What is the use of the split cells option?

Answer. Answer: Split cells is a feature that will allow you to divide a single column or row into more rows especially if you would like to fix some data in between the existing rows or columns.

What is the split cell?

Splitting cells is similar to adding a row or column, but it all takes place in one cell instead of a group of cells. Merging cells, however, is similar to deleting a cell and then adjoining it with a neighboring cell.

How will you calculate the sum in table?

Click the table cell where you want your result to appear. On the Layout tab (under Table Tools), click Formula. In the Formula box, check the text between the parentheses to make sure Word includes the cells you want to sum, and click OK. =SUM(ABOVE) adds the numbers in the column above the cell you’re in.

How do I create a border?

Add a border

1. Open Microsoft Word.
2. Click the Page Layout tab.
3. In the Page Background group, click the Page Borders option.
4. In the Borders and Shading window (shown below), if not already selected, click the Page Border tab.
5. Select Box if you want a square border around your page.

How do I put a border on my table?

To add a border to your table, you need to define the

Presentation on theme: «Word Equations Lesson 10.»— Presentation transcript:

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Word Equations Lesson 10

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A word equation is a way of representing a chemical reaction: it tells you what reacts and what is produced. Word equations are an efficient way to describe chemical changes, to help chemists recognise patterns, and to predict the products of a chemical reaction.

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Writing word equations
They are written in a particular order. Reactants (what you start with) are always on the left side of the arrow and products (what you make) are always on the right side of the arrow. Multiple reactants or products are separated by a + sign.

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Word Equations examples. Reactants Products
Silver nitrate + copper  silver + copper (II) nitrate  Reactants Products Hydrogen + Oxygen  water vapour Reactants Products

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The Conservation of Mass
In a chemical reaction, the total mass of the reactants is always equal to the total mass of the products. This tells us a few things. Atoms do not change in a reaction. The molecules that they form can be changed but the atoms themselves are not. Mass cannot be destroyed. If it could we could use E = MC2 to create energy

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Example Methane + oxygen  water + carbon dioxide

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Skeleton equations + Balancing Equations
A representation of a chemical reaction where the formulas of the reactants are connected to the formulas of the products by an arrow. CH4 + O2  H2O + CO2 This however does not demonstrate the Law of Conservation of Mass. The law states that the mass of the products will equal the mass of the reactants.

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Combustion of methane (the above reaction)
Type of atom Reactants Products C 1 H 4 2 O 2 + 1 = 3

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We can’t change the formulas of the products or reactants so the only thing we can do is change the number of molecules instead of their formulas.

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CH4 + O2 + O2  H2O +H2O + CO2 = CH4 + 2O2  2H2O + CO2
Now the chemical equation is balanced and the mass of the reactants will equal the mass of the products. Type of atom Reactants Products C 1 H 4 O = 4

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Steps to balancing an equation
Write the word equation of the reaction Aluminum + bromine  aluminum bromide Step 2 Write the skeleton equation by replacing each name with a correct formula. Al +Br2  AlBr3

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Steps to balancing an equation
Count the number of atoms on each side of the equation Type of atom Reactants Products Al 1 Br 2 3

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Steps to balancing an equation
Multiply each of the formulas by the appropriate coefficients to balance the number of atoms.

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Start out by picking the element with the most number of atoms and try to balance it first. We will start with Bromine. The 2 and 3 will be balanced if we multiply the reactant side by 3 which would give it 6 Br, and multiply the product side by 2 to give us 6 Br. Now we have 2 Al products which need to be balanced so we add a 2 to the Al on the reactant side. 2Al + 3Br2  2AlBr3

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More examples on the board
Hydrogen gas + Chlorine gas  hydrogen chloride Sodium + chlorine  sodium chloride Nitrogen + hydrogen  ammonia (hydrogen nitride) N2 + H2  NH3 = N2 + H2  NH3

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Complete the worksheet and hand in.