ed: Increase in weight Decrease in weight| Increase in weight :

Chemistry
10th Edition
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Chapter1: Chemical Foundations
Section: Chapter Questions
Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...
icon
Related questions
Question

need some help witht his pre lab

Preweighed samples of 3 salts were placed on separate watch glasses and allowed to
remain exposed to the air for 2 hr. At that time the following observations were
recorded:
Salt 1. Increase in weight and slightly moist
Salt 2. Decrease in weight and powdery
Salt 3. Increase in weight and significantly dissolved
For each salt, indicate whether it is a hydrate or anhydrous and whether it is deliquescent,
hygroscopic or efflorescent:
Salt 1
Salt 2
Salt 3
2.
A hydrated salt is 21% water (anhydrous formula weight is 136.1).
a. How many grams of water would be in 100.0 g of the hydrate?
b. How many grams of anhydrous salt would be in 100.0 g of the hydrate?
c. How many moles of the anhydrous salt would be in 100.0 g of the hydrate?
d. How many moles of water in 100.0 g of the hydrate?
3.
A student was given a sample of hydrated Na:CrO4 (molar mass of anhydrous Na2CrO4:
162.0 g/mol). She determined the weight of the hydrated sample to be 2.58 g. After
heating the hydrate to drive off all the water of hydration, she determined the weight of
the anhydrous salt to be 1.77 g. Calculate the formula of the hydrated salt (round to the
nearest whole number of water molecules/mol).
47
A 100.0-g sample of an unknown hydrate (formula weight 234.0 g/mol) contains 31.4 g
of water (formula weight 18.02). How many moles of water are there per mole of
hydrate?
Transcribed Image Text:Preweighed samples of 3 salts were placed on separate watch glasses and allowed to remain exposed to the air for 2 hr. At that time the following observations were recorded: Salt 1. Increase in weight and slightly moist Salt 2. Decrease in weight and powdery Salt 3. Increase in weight and significantly dissolved For each salt, indicate whether it is a hydrate or anhydrous and whether it is deliquescent, hygroscopic or efflorescent: Salt 1 Salt 2 Salt 3 2. A hydrated salt is 21% water (anhydrous formula weight is 136.1). a. How many grams of water would be in 100.0 g of the hydrate? b. How many grams of anhydrous salt would be in 100.0 g of the hydrate? c. How many moles of the anhydrous salt would be in 100.0 g of the hydrate? d. How many moles of water in 100.0 g of the hydrate? 3. A student was given a sample of hydrated Na:CrO4 (molar mass of anhydrous Na2CrO4: 162.0 g/mol). She determined the weight of the hydrated sample to be 2.58 g. After heating the hydrate to drive off all the water of hydration, she determined the weight of the anhydrous salt to be 1.77 g. Calculate the formula of the hydrated salt (round to the nearest whole number of water molecules/mol). 47 A 100.0-g sample of an unknown hydrate (formula weight 234.0 g/mol) contains 31.4 g of water (formula weight 18.02). How many moles of water are there per mole of hydrate?
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps

Blurred answer
Knowledge Booster
Vitamins and Coenzymes
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.
Similar questions
  • SEE MORE QUESTIONS
Recommended textbooks for you
Chemistry
Chemistry
Chemistry
ISBN:
9781305957404
Author:
Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:
Cengage Learning
Chemistry
Chemistry
Chemistry
ISBN:
9781259911156
Author:
Raymond Chang Dr., Jason Overby Professor
Publisher:
McGraw-Hill Education
Principles of Instrumental Analysis
Principles of Instrumental Analysis
Chemistry
ISBN:
9781305577213
Author:
Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:
Cengage Learning
Organic Chemistry
Organic Chemistry
Chemistry
ISBN:
9780078021558
Author:
Janice Gorzynski Smith Dr.
Publisher:
McGraw-Hill Education
Chemistry: Principles and Reactions
Chemistry: Principles and Reactions
Chemistry
ISBN:
9781305079373
Author:
William L. Masterton, Cecile N. Hurley
Publisher:
Cengage Learning
Elementary Principles of Chemical Processes, Bind…
Elementary Principles of Chemical Processes, Bind…
Chemistry
ISBN:
9781118431221
Author:
Richard M. Felder, Ronald W. Rousseau, Lisa G. Bullard
Publisher:
WILEY