Answer: Option (A) is the correct answer.
Explanation:
Atomic number of sodium is 11 and its electronic configuration is .
In order to gain stability, sodium loses one electron and hence it forms a positive ion .
Thus, we can conclude that when sodium combines with chlorine, it has a net charge of +1 because sodium loses a negative electron when forming chemical bonds.
Answer:
760 uM
Explanation:
<em>A biochemist carefully measures the molarity of magnesium ion in 47, mL of cell growth medium to be 97 uM. Unfortunately, a careless graduate student forgets to cover the container of growth medium and a substantial amount of the solvent evaporates. The volume of the cell growth medium falls to 6.0 mL. Calculate the new molarity of magnesium ion in the cell growth medium Be sure your answer has the correct number of significant digits.</em>
The problem here is that the amount of magnesium ion remains the same irrespective of the volume.
Amount of magnesium in the growth medium = <em>molarity x volume</em>
= 97 x x 47 x
= 4.559 x
Then, the volume reduced to 6.0 mL, the new molarity becomes;
<em>molarity = mole/volume </em>
= 4.559 x /6 x
= 7.598333 x
M = 759.83333 uM
To the correct number of significant digits = 760 uM
Answer: a) . Ammonia is the limiting reagent
b. Oxygen is left over and 0.1375 g of oxygen is left over.
c. The theoretical yield of is 35.29 g.
d. The theoretical yield of is 31.74 g.
Explanation:
To calculate the number of moles, we use the equation:
For
Given mass of ammonia = 20.0 g
Molar mass of ammonia = 17.031 g/mol
Putting values in equation 1, we get:
For
Given mass of oxygen gas = 50.0 g
Molar mass of oxygen gas = 32 g/mol
Putting values in equation 1, we get:
The chemical equation for the reaction is
By Stoichiometry of the reaction:
4 moles of ammonia reacts with = 5 moles of oxygen
So 1.17 moles of ammonia will react with = of oxygen
As, given amount of oxygen is more than the required amount. So, it is considered as an excess reagent and (1.6-1.4625)= 0.1375 g of oxygen is left unreacted.
Thus ammonia is considered as a limiting reagent because it limits the formation of product.
1. By Stoichiometry of the reaction:
4 moles of ammonia produces = 4 moles of
1.17 moles of ammonia will produce = of
Mass of
Thus Theoretical yield of is 35.29 grams.
2. By Stoichiometry of the reaction:
4 moles of ammonia produces = 6 moles of
1.2 moles of ammonia will produce = of
Mass of
Thus Theoretical yield of is 31.74 grams.