/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 8 State the number of significant ... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

State the number of significant figures in each of the following numbers: (a) \(40.0\) (b) \(0.081\) (c) 129,042 (d) \(4.090 \times 10^{-3}\)

Short Answer

Expert verified
3, 2, 6, 4

Step by step solution

01

Identifying significant figures in 40.0

The number 40.0 has three digits. To determine the number of significant figures, note that trailing zeros to the right of the decimal point are significant. Thus, 40.0 has three significant figures.
02

Identifying significant figures in 0.081

The number 0.081 has three digits. Leading zeros are not significant, but the digits after the leading zeros are significant. Thus, 0.081 has two significant figures.
03

Identifying significant figures in 129,042

The number 129,042 has six digits and contains no decimal point. All the digits are significant. Therefore, 129,042 has six significant figures.
04

Identifying significant figures in 4.090 x 10^{-3}

For the number 4.090 x 10^{-3}, only the digits in 4.090 are considered for significant figures. The scientific notation part (10^{-3}) does not affect the count of significant figures. Therefore, 4.090 has four significant figures.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

significant figures
In chemistry, significant figures reflect the precision of a number. They include all the non-zero digits, any zeros between these digits, and any trailing zeros when they are to the right of the decimal point.
Let's break it down:
  • Non-zero digits are always significant. For instance, in 129,042, each digit is counted.
  • Zeros between non-zero digits are significant. Take 4.090, where all zeros between 4 and 9 count.
  • Leading zeros before non-zero digits are not significant. For example, in 0.081, the zeros before 8 are not counted.
  • Trailing zeros in a number with a decimal point are significant. In 40.0, the zeros after the decimal count.
Understanding these rules helps you interpret measurements accurately.
leading zeros
Leading zeros appear before the first non-zero digit. They don't contribute to the number of significant figures. They only serve as place holders.
For example:
  • In the number 0.081, the zeros before 8 are leading zeros, making only 8 and 1 significant.
These rules ensure precision is maintained and numbers are interpreted correctly. Even when written in scientific notation, such as 4.090 × 10^{-3}, leading zeros are ignored.
trailing zeros
Trailing zeros are zeros that follow a non-zero digit. Their significance depends on the presence of a decimal point.
If a decimal is present:
  • Trailing zeros are significant. For example, in 40.0, all digits are significant, making it three significant figures.
If a decimal is absent:
  • Trailing zeros are not significant. For example, 4000 would only have one significant figure unless further specified.
This rule helps scientists communicate precise measurements and avoid ambiguity.
scientific notation
Scientific notation is a way to express very large or very small numbers in a more concise form. Significant figures in numbers written this way are determined by the digits before the multiplication sign.
For instance:
  • In 4.090 × 10^{-3}, focus on 4.090. It has four significant figures.
  • The exponent (10^{-3}) does not impact the significant figures count.
Scientific notation helps in maintaining precision and readability of measurements, which is fundamental in chemistry.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Dark-roasted coffee contains increased amonts of Nmethylpyridinium, or NMP, a ringed compound that is not present in green unroasted coffee beans. This compound seems to decrease the stomach acid production normally associated with drinking coffee. In coffee made from dark-roasted coffee, the concentration of NMP is \(31.4 \mathrm{mg} / \mathrm{L}\). How many milligrams of NMP would you consume if you drank \(2.00\) large cups of dark-roasted coffee? (One coffee cup contains \(10.0\) fluid ounces of liquid.)

In 2005 , Jarno Trulli was the pole winner of the U.S. Grand Prix Race with a speed of \(133 \mathrm{mi}\) per hr. What was his speed in \(\mathrm{cm} / \mathrm{s}\) ?

Round each of the following numbers to three significant figures: (a) \(8.8726\) (b) \(21.25\) (c) \(129.509\) (d) \(1.995 \times 10^{6}\)

You decide to go sailing in the tropics with some friends. Once there, you listen to the marine forecast, which predicts in-shore wave heights of \(1.5 \mathrm{~m}\), offshore wave heights of \(4 \mathrm{~m}\), and temperature of \(27^{\circ} \mathrm{C}\). Your friend the captain is unfamiliar with the metric system, and he needs to know whether it is safe for your small boat and if it will be warm. He asks you to convert the measurements to feet and degrees Fahrenheit, respectively.

A solution is prepared by dissolving \(95.4\) grams of sodium nitrate in 753 grams of water. (a) What is the percent sodium nitrate in the solution? (b) If 350 . grams of the solution are poured into a beaker, how many grams of sodium nitrate are introduced into the beaker? (c) How many grams of the solution are required to obtain \(50.0\) grams of sodium nitrate?

See all solutions

Recommended explanations on Chemistry Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.