Answer:
v = 658.82 km/h
Explanation:
The distance between New York and London is 
Time taken from New York to London is 8.5 hours
We need to find the average speed of the plane.
Total distance covered divided by the total time taken is equal to the average speed of an object. So,

So, the average speed of the plane is 658.82 km/h.
Answer:
Percentage abundance of 121 Sb is = 57.2 %
Percentage abundance of 123 Sb is = 42.8 %
Explanation:
The formula for the calculation of the average atomic mass is:
Given that:
Since the element has only 2 isotopes, so the let the percentage of first be x and the second is 100 -x.
For first isotope, 121 Sb :
% = x %
Mass = 120.9038 u
For second isotope, 123 Sb:
% = 100 - x
Mass = 122.9042 u
Given, Average Mass = 121.7601 u
Thus,

Solving for x, we get that:
x = 57.2 %
<u>Thus, percentage abundance of 121 Sb is = 57.2 %
</u>
<u>percentage abundance of 123 Sb is = 100 - 57.2 % = 42.8 %</u>
Answer:
Radium
Explanation:
It has the highest atomic number so it would have more shells, making it larger than the others.
Answer:
Required Volume is 22.47ml
Explanation:
To make 2.0L of 0.2M sulfuric acid required moles = 0.2 x 2 = 0.4 moles
To get 0.4 from 17.8M required quantity = 1000/17.8 x 0.4 = 22.47ml
The balanced reaction is:<span>
Mg (s) + 2HCl (aq)
--> MgCl 2 (aq) + H 2 (g)
We
are given the amount hydrochloric acid to be used for the reaction. This will
be the starting point of the calculation.
40.0 g
HCl ( 1 mol HCl / 36.46 g HCl)
(1 mol H2 / 2 mol HCl) (2.02 g H2 / 1 mol H2) = 1.11 g H2</span>