A)Constant pumping from the heart which provides adequate pressure necessary to move the blood through the arteries and veins
B)Gravitational force
The mass percentage is 15.1465%.
“Star cluster” is a generic way for astronomers to refer to a group of stars that formed from the same material and are gravitationally bound for at least some period of time. There are two major types of star clusters — globular clusters and open clusters — and they are actually quite different.
Answer: X3+
Explanation:
Every atom aim to achieve stability by receiving electrons or giving their valence electrons in order to have a complete outermost shell of 2 (duplet) or 8 (octet structure).
In this case, the atom X will easily give off its three valence electrons to another atom(s), thereby forming a trivalent positive ion (X3+) with a stable duplet or octet structure (i.e an outermost shell with 2 or 8 electrons).
X --> X3+ + 3e-
Thus, due to the give away of three electrons (3e-), the atom X becomes X3+.
<h2>Natural Abundance for 10B is 19.60%</h2>
Explanation:
- The natural isotopic abundance of 10B is 19.60%.
- The natural isotopic abundance of 11B is 80.40%.
- The isotopic masses of boron are 10.0129 u and 11.009 u respectively.
For calculation of abundance of both the isotopes -
Supposing it was 50/50, the average mass would be 10.5, so to increase the mass we need a more percentage of 11.
Determining it as an equation -
10x + 11y= 10.8
x+y=1 (ratio)
10x + 10y = 10
By taking the denominator away from the numerator
we get;
y = 0.8
x + y = 1
∴ x = 0.2
To get percentages we need to multiply it by 100
So, the calculated abundance is 80% for 11 B and 20% 10 B.