An 8.2420-gram sample of an unknown hydrate of cobalt(II) bromide is heated until all the water...
Question:
An 8.2420-gram sample of an unknown hydrate of cobalt(II) bromide is heated until all the water of hydration is removed. The {eq}CoBr_2 {/eq} that remains has a mass of 6.2000 grams.
a. How many moles of {eq}CoBr_2 {/eq} are in the sample?
b. How many grams of water were lost in the dehydration?
c. How many moles of water were lost?
d. What is the value of "{eq}n {/eq}" in the formula {eq}CoBr_2 \cdot nH_2O {/eq}?
Hydrated Salts:
Some compounds have the ability of absorb water to form hydrated salts. The water contained in hydrated salts is known as water of crystallization. Since the water molecules do not form chemical bonds with the salt in the hydrated salts, the water of crystallization can easily be removed by heating.
Answer and Explanation: 1
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{eq}\rm CoBr_2\cdot nH_2O \xrightarrow{heat} CoBr_2+nH_2O {/eq}
a. How many moles of {eq}\rm CoBr_2 {/eq} are in the sample?
The molar mass...
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Hydrates: Determining the Chemical Formula From Empirical Data
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Chapter 9 / Lesson 8
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Learn the anhydrate definition and what a hydrated compound is. Understand what an anhydrate is, the hydrate formula, and how to find the formula of the hydrate.
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