The answer & explanation for this question is given in the attachment below.
Answer:
72.67g of B
Explanation:
The reaction of B₂O₃ to produce boron (B), is:
B₂O₃ → 3/2O₂ + 2B
<em>That means B₂O₃ produce 2 moles of boron</em>
Molar mass of B₂O₃ is 69.62g/mol. 234g of B₂O₃ contains:
234g B₂O₃ ₓ (1mol / 69.62g) = 3.361 moles of B₂O₃.
As 1 mole of B₂O₃ produce 2 moles of B, Moles of B that can be produced from B₂O₃ is:
3.361mol B₂O₃ ₓ 2 = <em>6.722 moles of B</em>.
As molar mass of B is 10.811g/mol. Thus mass of B that can be produced is:
6.722mol B ₓ (10.811g / mol) = <em>72.67g of B</em>
Answer:
See explanation
Explanation:
The number of electrons in each principal energy shell increases as the number of shells increases because more electronic orbitals become available to accommodate the electrons.
For instance, the n= 2 level only accommodates eight electrons in the s and p orbitals whereas the n=3 level accommodates 18 electrons in s, p and d orbitals respectively.
Each principal level accommodates 2n^2 electrons where n= the principal energy shell.
Answer:
145 hours
Explanation:
Since one hour of riding a bicycle takes up 505 kcal of energy. It is also stated that one gram of body fat is equal to 7.70 kcal. Also, it is given that 1 pound of body fat is equal to 454 g.
Hence;
1 Ib= 454 g
21 Ib= 21 × 454/1 = 9534 g
But
1g of body fat = 7.70kcal
9534 g of body fat = 9534 × 7.70 kcal/1 = 73411.8 kcal
If 505 kcal is lost in 1 hour
73411.8 kcal is lost in 73411.8 kcal × 1hour/505k cal = 145 hours
There are 22.99073411 miles in 37 kilometers.
You would use the formula (Miles = Kilometers * 0.621371192) to get your answer.
Other calculations:
37 kilometer(s) = 40463.69 yards
37 kilometer(s) = 121391.08 feet or foot
37 kilometer(s) = 1456692.91 inches
Hope this helps! :)
