Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 3: Problem 88

A sample of urea contains $1.121 \mathrm{g} \mathrm{N}, 0.161 \mathrm{g} \mathrm{H}, 0.480 \mathrm{g} \mathrm{C}\( and 0.640 \)\mathrm{g}$ O. What is the empirical formula of urea?

Short Answer

Expert verified
The empirical formula of urea is \( \text{NH}_2\text{CO} \).

Step by step solution

01

Convert grams to moles

We have the grams for each element as follows: - Nitrogen (N): 1.121 g - Hydrogen (H): 0.161 g - Carbon (C): 0.480 g - Oxygen (O): 0.640 g Use the molar mass of each element to convert grams to moles: - Moles of N = \( \frac{1.121 \text{ g}}{14.01 \text{ g/mol}} \) - Moles of H = \( \frac{0.161 \text{ g}}{1.01 \text{ g/mol}} \) - Moles of C = \( \frac{0.480 \text{ g}}{12.01 \text{ g/mol}} \) - Moles of O = \( \frac{0.640 \text{ g}}{16.00 \text{ g/mol}} \)
02

Calculate the mole ratios

Now that we have the moles for each element, we will calculate the mole ratios. - Moles of N = \( \frac{1.121}{14.01} = 0.080 \) - Moles of H = \( \frac{0.161}{1.01} = 0.160 \) - Moles of C = \( \frac{0.480}{12.01} = 0.040 \) - Moles of O = \( \frac{0.640}{16.00} = 0.040 \)
03

Determine the simplest whole-number ratio

Next, we need to derive the simplest whole-number ratio between the mole ratios calculated in Step 2. Divide each mole ratio by the smallest one, which in this case is 0.040 (moles of Carbon and Oxygen): - Ratio for N = \( \frac{0.080}{0.040} = 2 \) - Ratio for H = \( \frac{0.160}{0.040} = 4 \) - Ratio for C = \( \frac{0.040}{0.040} = 1 \) - Ratio for O = \( \frac{0.040}{0.040} = 1 \)
04

Write the empirical formula

Lastly, we will write the empirical formula using the simplest whole number ratio obtained in Step 3: The empirical formula of urea is: \( \text{NH}_2\text{CO} \)

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.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

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

An ionic compound \(\mathrm{MX}_{3}\) is prepared according to the following unbalanced chemical equation. $$ \mathrm{M}+\mathrm{X}_{2} \longrightarrow \mathrm{MX}_{3} $$ A 0.105 -g sample of \(\mathrm{X}_{2}\) contains \(8.92 \times 10^{20}\) molecules. The compound \(\mathrm{MX}_{3}\) consists of 54.47$\% \mathrm{X} \mathrm{by}\( mass. What are the identities of \)\mathrm{M}\( and \)\mathrm{X}$ , and what is the correct name for \(\mathrm{MX}_{3} ?\) Starting with 1.00 \(\mathrm{g}\) each of \(\mathrm{M}\) and \(\mathrm{X}_{2},\) what mass of \(\mathrm{MX}_{3} \mathrm{can}\) be prepared?

ABS plastic is a tough, hard plastic used in applications requiring shock resistance. The polymer consists of three monomer units: acrylonitrile \(\left(\mathrm{C}_{3} \mathrm{H}_{3} \mathrm{N}\right),\) butadiene \(\left(\mathrm{C}_{4} \mathrm{H}_{6}\right),\) and styrene \(\left(\mathrm{C}_{8} \mathrm{H}_{8}\right)\) a. A sample of ABS plastic contains 8.80\(\% \mathrm{N}\) by mass. It took 0.605 \(\mathrm{g}\) of \(\mathrm{Br}_{2}\) to react completely with a \(1.20-\mathrm{g}\) sample of \(\mathrm{ABS}\) plastic. Bromine reacts \(1 : 1\) (by moles) with the butadiene molecules in the polymer and nothing else. What is the percent by mass of acrylonitrile and butadiene in this polymer? b. What are the relative numbers of each of the monomer units in this polymer?

Para-cresol, a substance used as a disinfectant and in the manufacture of several herbicides, is a molecule that contains the elements carbon, hydrogen, and oxygen. Complete combustion of a \(0.345-\mathrm{g}\) sample of \(p\) -cresol produced 0.983 g carbon dioxide and 0.230 \(\mathrm{g}\) water. Determine the empirical formula for \(p\) -cresol.

A given sample of a xenon fluoride compound contains molecules of the type \(\mathrm{XeF}_{n},\) where \(n\) is some whole number. Given that $9.03 \times 10^{20}\( molecules of \)\mathrm{XeF}_{n}\( weigh \)0.368 \mathrm{g},$ determine the value for \(n\) in the formula.

Balance the following equations: a. $\operatorname{Cr}(s)+\mathrm{S}_{8}(s) \rightarrow \mathrm{Cr}_{2} \mathrm{S}_{3}(s)$ b. \(\operatorname{NaHCO}_{3}(s) \stackrel{\mathrm{Heat}}{\longrightarrow}\) $\mathrm{Na}_{2} \mathrm{CO}_{3}(s)+\mathrm{CO}_{2}(g)+\mathrm{H}_{2} \mathrm{O}(g)$ c. \(\quad \mathrm{KClO}_{3}(s) \stackrel{\mathrm{Heat}}{\longrightarrow}\) \(\mathrm{KCl}(s)+\mathrm{O}_{2}(g)\) d. $\operatorname{Eu}(s)+\mathrm{HF}(g) \rightarrow \operatorname{EuF}_{3}(s)+\mathrm{H}_{2}(g)$
See all solutions

Recommended explanations on Chemistry Textbooks

Inorganic Chemistry

Read Explanation

Nuclear Chemistry

Read Explanation

Chemical Reactions

Read Explanation

Chemical Analysis

Read Explanation

Physical Chemistry

Read Explanation

Making Measurements

Read Explanation
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.

Sign-up for free