The unit M means that mole/L, So first change the unit of solution volume to L which is 0.25 L. So the mole of solute is 2.5*0.25=0.625 mol.
Answer:
(B.) and (C.)
b. So that clean NMR spectra can be obtained that do not contain solvent peaks.
c. So that the yield can be determined.
Explanation:
The solvent used in Nuclear Magnetic Resonance (NMR) spectrometer is Trimethyl silane (TMS), a neutral solvent which doesn't give off any signals. Other solvents could have interactions with the radiation, and disrupt the spectra.
Furthermore, for accurate determination of the actual yield and overall percentage yield, solid must be separated from the solvent, dried and weighed.
I hope this was explanatory enough.
The answers for the following questions is answered below.
- Therefore the volume of a gas is 22.4 L
- <u>Therefore the number of moles of oxygen are 2.37 moles</u>
Explanation:
1. Given:
no of molecules (n) = 6.023 × 
volume of gas at STP conditions (V) =22.4 liters
To solve:
Volume of gas (v)
We know;


1 × 22.4 = v
v =22.4 L
Therefore the volume of a gas is 22.4 L
2. Given:
volume of oxygen gas (v) = 53 L
Volume of gas at STP conditions (V) =22.4 L
To solve:
no of moles of oxygen gas
We know;

n =
n =2.37 moles
<u>Therefore the number of moles of oxygen are 2.37 moles</u>
<u></u>
Answer:
28 g solute per 100 g of solution
Explanation:
28% mass means that in all your solution you have 28% of your solute, you could use grames/grames, ml/ml or whatever you want to. So if you are working with a 100 grams solution, 28 grams of that solution must be solute if you want a 28% mass. So, the correct answer is 28 g solute per 100 g of solution.
<h3>
Answer:</h3>
156 calories
<h3>
Explanation:</h3>
- Carbohydrates, proteins and fats are food substances used by living organisms to generate energy required for the day to day activities.
- They supply energy which differs per gram for each food substance.
- That is;
1 g of carbohydrate = 4 calories
1 g of fat = 9 calories
1 g of protein = 4 calories
Therefore, whole milk serving containing 8.0 g of fat, 8.0 g of protein and 13 g of carbohydrates will contain the following number of calories;
8.0 g of fat = 8 g × 9 cal/g = 72 calories
8.0 g of protein = 8 g × 4 cal/g = 32 calories
13 g of carbohydrates = 13 g × 4 cal/g = 52 calories
Total amount of energy = 156 calories
Therefore, an 8 oz serving of whole milk contains 156 calories