Answer:
0.70 g
41 %
Explanation:
We can write the Williamson ether synthesis in a general form as:
R-OH + R´-Br ⇒ R-O-R´
where R-OH is an alcohol and R´-Br is an alkyl bromide.
We then see that the reaction occurs in a 1:1 mole ratio to produce 1 mol product.
Therefore what we need to calculate the theoretical yield and percent yield is to compute the theoretical number of moles of 2-butoxynaphthalene produced from 0.51 g 2-naphthol, and from there we can calculate the percent yield.
molar mass 2-naphthol = 144.17 g/mol
moles 2-naphthol = 0.51 g / 144.17 g/mol = 0.0035 mol 2-naphthol
The number of moles of produced:
= 0.0035 mol 2-naphthol x ( 1 mol 2-butoxynaphthalene /mol 2-naphthol )
= 0.0035 mol 2-butoxynaphthalene
The theoretical yield will be
= 0.0035 mol 2-butoxynaphthalene x molar mass 2-butoxynaphthalene
= 0.0035 mol x 200.28 g/ mol = 0.70 g
percent yield= ( 0.29 g / 0.70 ) g x 100 = 41 %
Answer:
64.0
Explanation:
2Mg+O2 ---> 2MgO
use dimentional analysis to find the amount of moles of O2 needed first
4.00molMg x 1.00mol O2/ 2.00 mol Mg=. 2.00 mol O2
using the coefficients you can see the mole ratio for O2:Mg the mole ratio is 1:2 which is why there is 1 mole on the top for 2 moles on the bottom. The Mg would cancel and multiply 4 by 1 then divide by 2, or multipy 4 by 1/2
Now that you have the moles of O2 you use the molar mass to find the grams in 2 moles of O2
2.00 mol O2 x 32.0g/1.00 mol = 64.0 g
multiply 2 by 32
Answer: Option (a) is the correct answer.
Explanation:
At low pressure and high temperature there exists no force of attraction or repulsion between the molecules of a gas. Hence, gases behave ideally at these conditions.
Whereas at low temperature there occurs a decrease in kinetic energy of gas molecules and high pressure causes the molecules to come closer to each other.
As a result, there exists force of attraction between the molecules at low temperature and high pressure and under these conditions gases are known as real gases.
Thus, we can conclude that the ideal gas law tends to become inaccurate when the pressure is raised and the temperature is lowered.
A compound is a substance that is made up of two or more elements that are chemically combined. A polyatomic ion is also known as a molecular ion, is a charged chemical species composed of two or more atoms. For example a nitrate ion (NO3-) is an example of a polyatomic ion in that it contains a nitrogen atom and three oxygen atoms bonded covalently to each other and act as a single charged unit. Therefore, appropriate answer would be a polyatomic ion or a molecular ion
