科学家和工程师经常用非常大或非常小的数字工作，这些数字更容易用指数形式或科学符号来表示。用科学符号书写的数字的一个经典的化学例子是Avogadro的数（6.022×1023）。科学家通常使用光速（3.0x 108 m/s）进行计算。一个非常小的数的例子是电子的电荷（1.602x 10-19库仑）。通过向左移动小数点直到只剩下一个数字，就可以用科学的记数法写出大量的数字。小数点的移动数给出一个指数，对于大数它总是正的。例如：3454000＝3.454×106。对于非常小的数字，将小数点移动到右边，直到小数点左边只剩下一个数字。向右移动的数目给出一个负指数：0.0000005234=5.234×10-7。并非所有计算器都能处理科学符号，但是您可以在科学计算器上轻松地执行科学符号计算。要输入数字，请查找^按钮，它表示“升到幂”，或者y x或x y，它表示y分别升到幂x或升到y的x。另一个常见的按钮是10X，这使得科学的注释变得容易。这些按钮函数的方式取决于计算器的品牌，所以您需要阅读说明书或者测试函数。您要么按10x然后输入x的值，要么输入x值然后按10x按钮。用一个你知道的数字测试这个，来掌握它的诀窍。还要记住，不是所有的计算器都遵循运算的顺序，其中乘法和除法是在加法和减法之前执行的。如果您的计算器有括号，最好使用它们来确保正确地执行计算。
Scientists and engineers often work with very large or very small numbers, which are more easily expressed in exponential form or scientific symbols. A classic chemical example of numbers written in scientific symbols is the number of Avogadro (6.022 x 1023). Scientists usually use the speed of light (3.0x 108 m/s) to calculate. An example of a very small number is the charge of the electron (1.602x 10-19 coulombs). By moving decimal points to the left until only one number is left, a large number of numbers can be written in scientific notation. The moving number of decimal points gives an exponent, which is always positive for large numbers. For example, 3454000 = 3.454 x 106. For very small numbers, move the decimal point to the right until there is only one left decimal point. The number of right-moving gives a negative index: 0.0000005234 = 5.234 x 10-7. Not all calculators can handle scientific symbols, but you can easily perform scientific symbolic computation on a scientific calculator. To enter a number, look for the ^ button, which means “go up to power”, or Y X or X y, which means y goes up to power X or X goes up to y, respectively. Another common button is 10X, which makes scientific annotations easy. The way these button functions work depends on the brand of the calculator, so you need to read the instructions or test functions. You can either press 10x and enter the value of x, or enter the value of X and press the 10x button. Test this with a number you know to get the hang of it. Also remember that not all calculators follow the order of operations, where multiplication and division are performed before addition and subtraction. If your calculators have parentheses, it’s best to use them to ensure that calculations are performed correctly.