科学家和工程师经常使用非常大或非常小的数字,这些数字更容易以指数形式或科学记数法表达。用科学记数法编写的数字的经典化学例子是Avogadro的数字(6.022 x 1023)。科学家通常使用光速(3.0 x 108 m / s)进行计算。极少数的例子是电子的电荷(1.602×10-19库仑)。通过将小数点向左移动直到左边只剩下一个数字,您可以用科学记数法写出一个非常大的数字。小数点的移动次数为您提供指数,对于大数字,该指数始终为正数。例如:3,454,000 = 3.454 x 106对于非常小的数字,您将小数点向右移动,直到小数点左侧只剩下一位数字。向右移动的次数给出一个负指数:0.0000005234 = 5.234 x 10-7并非所有计算器都能处理科学计数法,但您可以在科学计算器上轻松执行科学计数法计算。要输入数字,请查找^按钮,这意味着“提升到幂”或者yx或xy,这意味着y分别上升到幂x或x上升到y。另一个常见按钮是10x,这使得科学记数容易。这些按钮功能的方式取决于计算器的品牌,因此您需要阅读说明或测试功能。您将按10x然后输入x的值,否则输入x值然后按10x按钮。用你知道的数字测试它,以获得它的悬念。还要记住并非所有计算器都遵循操作顺序,其中在加法和减法之前执行乘法和除法。如果您的计算器有括号,最好使用它们来确保正确执行计算。

美国麦肯纳学院化学Assignment代写:化学中的科学记数法

Scientists and engineers often work with very large or very small numbers, which are more easily expressed in exponential form or scientific notation. A classic chemistry example of a number written in scientific notation is Avogadro’s number (6.022 x 1023). Scientists commonly perform calculations using the speed of light (3.0 x 108 m/s). An example of a very small number is the electrical charge of an electron (1.602 x 10-19 Coulombs). You write a very large number in scientific notation by moving the decimal point to the left until only one digit remains to the left. The number of moves of the decimal point gives you the exponent, which is always positive for a big number. For example: 3,454,000 = 3.454 x 106 For very small numbers, you move the decimal point to the right until only one digit remains to the left of the decimal point. The number of moves to the right gives you a negative exponent: 0.0000005234 = 5.234 x 10-7 Not all calculators can handle scientific notation, but you can perform scientific notation calculations easily on a scientific calculator. To enter in the numbers, look for a ^ button, which means “raised to the power of” or else yx or xy, which means y raised to the power x or x raised to the y, respectively. Another common button is 10x, which makes scientific notation easy. The way these button function depends on the brand of calculator, so you’ll need to either read the instructions or else test the function. You will either press 10x and then enter your value for x or else you enter the x value and then press the 10x button. Test this with a number you know, to get the hang of it. Also remember not all calculators follow the order of operations, where multiplication and division are performed before addition and subtraction. If your calculator has parentheses, it’s a good idea to use them to make certain the calculation is carried out correctly.