<u>Given:</u>
Mass = 68 kg
Power = 65 W
<u>To determine:</u>
Calories burned during an 8.0 hr sleep
<u>Explanation:</u>
Energy is expressed as:
Energy = Power * Time
Now, the unit of power = Watt (W)
1 W = 1 J/s i.e. 65 W = 65 J/s
Time = 8 hrs = 8 * 3600 s = 28800 s
Energy = 65 J/s * 28800 s = 1872000 J
Convert Joules (J) to calories (cal)
1 cal = 4.184 J
The calculated energy = 187200 J * 1 cal/4.184 = 447418 cal
Ans: The man burns nearly 447.4 kcal during an 8 hr sleep
Answer:
The answer to your question is 150 ml
Explanation:
Data
Volume 1 = 25 ml
Concentration 1 = 0.6 M
Volume 2 = ?
Concentration 2 = 0.1 M
Formula
Volume 1 x Concentration 1 = Volume 2 x Concentration 2
Solve for Volume 2
Volume 2 = (Volume 1 x Concentration 1)/Concentration 2
Substitution
Volume 2 = (25 x 0.6) / 0.1
Simplification
Volume 2 = 15 / 0.1
Result
Volume 2 = 150 ml
<span>PBr5
You started with 0.72 mg of phosphorus and ended up with 10.01 mg of its bromide. So the amount of bromine is 10.01 - 0.72 = 9.29 mg
Now you need to determine the relative number of atoms of each element used.
atomic mass of phosphorus = 30.973762
atomic mass of bromine = 79.904
relative atoms of phosphorus = 0.72 / 30.973762 = 0.023245
relative atoms of bromine = 9.29 / 79.904 = 0.116265
Now you need to look for a simple ratio of integers that closely approximates 0.023245 / 0.116265. First we'll divide the larger by the smaller.
0.116265 / 0.023245 = 5.001597
Given how close the value comes to 5. The empirical formula will be PBr5. So for every atom of phosphorus, you need 5 atoms of bromine.</span>
