K.+Soo+Synthesis+reaction.

= = =** Synthesis Reaction. **= ==

In a synthesis reaction, also known as a composition reaction, two or more substances combine to produce a single compound.

 A + B —› AB 

** Example of a synthesis reaction. **
Hydrogen gas combines with oxygen gas to produce dihydrogen monoxide (water).

** Changing the word equation into a formula equation… **
To change the word equation into a formula equation of the reaction, the first thing you need to know is the element’s atomic symbol. By checking the periodic table of elements, you know that hydrogen is represented by “H” and oxygen, “O”. Using the atomic symbols, write a formula equation: H + O —›  H2O    Because both hydrogen and oxygen are diatomic molecules, they must consist of two atoms of the same element when not combined with any other elements. This is why you need to add a subscript of 2 after the H and the O... H  2 + O 2  —› H2O

The equation is not yet balanced because the number of hydrogens and oxygens on either side of the arrow are not equal. Start by putting a coefficient of 2 before the H2O... H2 + O2 —› 2 H2O Placing the coefficient of 2 before the H2O multiplies everything in the compound by 2, meaning that the product now has 4 hydrogen atoms and 2 oxygen atoms.

Although there are an equal number of oxygens on either side of the equation, the number of hydrogens is not equal because there are 4 hydrogen atoms in the product, but only 2 on the left. To correct this, you need to put a coefficient in front of the reactant, H2, remember that you cannot change the subscript, only the coefficient.  2 H2 + O2 —› 2 H2O This is the final formula equation for water, the equation is now balanced! There are an equal number of hydrogen and oxygen atoms on either side of the formula.

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