Answer:
The correct answer to the following question will be "62.9 %".
Explanation:
The given values are:
The aspirin's initial amount = 5.945 g.
and is polluted containing 2,134 g of sodium sulfate.
After extraction we provided 3,739 g of pure aspirin.
Now,
On putting the values in the above formula, we get
⇒ 
⇒ 
Note: percent = %
Answer:
b) 2.0 mol
Explanation:
Given data:
Number of moles of Ca needed = ?
Number of moles of water present = 4.0 mol
Solution:
Chemical equation:
Ca + 2H₂O → Ca(OH)₂ + H₂
now we will compare the moles of Ca and H₂O .
H₂O : Ca
2 : 1
4.0 : 1/2×4.0 = 2.0 mol
Thus, 2 moles of Ca are needed.
Answer:
90.3 L
Explanation:
Given data:
Volume of water produced = 77.4 L
Volume of oxygen required = ?
Solution:
Chemical equation:
2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O
It is known that,
1 mole = 22.414 L
There are 7 moles of oxygen = 7×22.414 = 156.9 L
There are 6 moles of water = 6×22.414 = 134.5 L
Now we will compare:
H₂O : O₂
134.5 : 156.9
77.4 : 156.9/134.5×77.4 =90.3 L
So for the production of 77.4 L water 90.3 L oxygen is required.
Melting point- the temperature at which a substance has changed from a solid to a liquid
freezing- the temperature at which a substance chanes from liquid to a solid
boiling point- the temperature at which a substance changes from a liquid to a gas phase
Answer:
c. 2NH₃ + 2H₂O + Cu²⁺ → Cu(OH)₂(s) + 2NH₄⁺
Explanation:
A net ionic equation is a chemical equation that list only the species that are involved in the reaction.
The reaction of ammonia with copper(II) sulfate CuSO₄ in water is:
2NH₃ + 2H₂O + CuSO₄ → Cu(OH)₂(s) + 2NH₄⁺ + SO₄²⁻
In an ionic equation, salts are written as ions, that means CuSO₄ must be written as Cu²⁺ + SO₄²⁻. That is:
2NH₃ + 2H₂O + Cu²⁺ +<u> SO₄²⁻</u> → Cu(OH)₂(s) + 2NH₄⁺ + <u>SO₄²⁻</u>
As in a net ionic equation you must list only the species involved in the reaction (The underlined species don't react), the net ionic equation is:
<em>c</em>. <em>2NH₃ + 2H₂O + Cu²⁺ → Cu(OH)₂(s) + 2NH₄⁺</em>
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I hope it helps!
