Answer:
0.59 moles
Explanation:
Data Given
oxygen = 35 g
Moles of SeO₃ = ?
Reaction Given
2Se + 3O₂ ------> 2SeO₃
Solution:
Step 1.
First to find grams of SeO₃
So, we know from reaction that 2 mole of selenium combine with 3 mole of oxygen and produces 2 mole of SeO₃
2Se + 3O₂ ------> 2SeO₃
2mol 3 mol 2 mol
If we represent mole in grams
Then,
Molar mass of Se = 79 g/mol
Molar mass of O = 16 g/mol
Molar mass of SeO₃ = 79 + 3(16)
Molar mass of SeO₃ = 127 g/mol
2Se + 3O₂ ------> 2SeO₃
2mol (79 g/mol) 3 mol (32 g/mol) 2 mol (127 g/mol)
2Se + 3O₂ ------> 2SeO₃
158 g 96 g 206 g
It is obvious from the reaction that 96 g of oxygen gives 206 g of SeO₃.
Now how many grams of SeO₃ will produce if 35 grams of oxygen react with excess of Selenium
Apply unity formula
96 g of O₂ ≅ 206 g of SeO₃
35 g of O₂ ≅ x g of SeO₃
By doing cross multiplication
g of SeO₃ = 206 x 35 / 96
g of SeO₃ = 75 g
Step 2.
Convert grams of SeO₃ to mole
Formula used
no. of moles = mass in grams (SeO₃) / Molar mass of SeO₃
Put values in above formula
no. of moles = 75 g / 127 g/mol
no. of moles = 0.59 mol
So,
35 g of oxygen produces 0.59 moles of SeO₃
A
Bronsted-Lowry acid is a proton donor (usually hydrogen ion). And a
Bronsted-Lowry base is a proton acceptor (usually hydrogen ion). Consider a
chemical reaction between HCl and NaOH. We have the reaction HCl + NaOH à NaCl + H2O. The
hydroxide ions in the NaOH are bases because they accept hydrogen ions from
acids to form water. And an acid produces hydrogen ions in solution by giving a
proton to the water molecule. Therefore, the answer is d. a Bronsted-Lowry
base.
Answer: 78.69 g of Fe
Explanation: Iron(III) oxide is Fe2O3. It has a molar mass of 159.7 g/mole. That consists of:
2 x Fe at 55.85 = 11.69 or 69.94%
3 x O at 16.0 = 48.0 or 30.06%
Therefore 112.5 grams will contain (112.5 g)*(69.94%) = 78.69 g of Fe
A double bond in chemistry is a chemical bond between two chemical elements involving four bonding electrons<span> instead of the usual two. The most common double bond, that is between two </span>carbon atoms<span>, can be found in </span>alkenes<span>. Many types of double bonds exist between two different elements.</span>
Answer:
<u>B. 2</u>
Explanation:
A single bond contains <u>2</u> shared electrons.
Given example is that of <u>ethane</u>