Answer:
![\boxed {\boxed {\sf 1.393 *10^{24} \ atoms \ B}}](https://tex.z-dn.net/?f=%5Cboxed%20%7B%5Cboxed%20%7B%5Csf%201.393%20%2A10%5E%7B24%7D%20%5C%20atoms%20%5C%20B%7D%7D)
Explanation:
<u>1. Convert Grams to Moles</u>
Use the molar mass (found on the Periodic Table) to convert from grams to moles.
Use this value as a ratio.
![\frac {10.81 \ g \ B }{1 \ mol \ B}](https://tex.z-dn.net/?f=%5Cfrac%20%7B10.81%20%5C%20g%20%5C%20B%20%7D%7B1%20%5C%20mol%20%5C%20B%7D)
Multiply by the given number of grams.
![25.00 \ g \ B *\frac {10.81 \ g \ B }{1 \ mol \ B}](https://tex.z-dn.net/?f=25.00%20%5C%20g%20%5C%20B%20%2A%5Cfrac%20%7B10.81%20%5C%20g%20%5C%20B%20%7D%7B1%20%5C%20mol%20%5C%20B%7D)
Flip the ratio so the grams of boron cancel out.
![25.00 \ g \ B *\frac {1 \ mol \ B }{10.81 \ g \ B}](https://tex.z-dn.net/?f=25.00%20%5C%20g%20%5C%20B%20%2A%5Cfrac%20%7B1%20%20%5C%20mol%20%5C%20B%20%7D%7B10.81%20%5C%20g%20%5C%20B%7D)
![25.00 *\frac {1 \ mol \ B }{10.81 }](https://tex.z-dn.net/?f=25.00%20%2A%5Cfrac%20%7B1%20%20%5C%20mol%20%5C%20B%20%7D%7B10.81%20%7D)
![\frac {25.00 \ mol \ B }{10.81 }=2.312673451 \ mol \ B](https://tex.z-dn.net/?f=%5Cfrac%20%7B25.00%20%5C%20mol%20%5C%20B%20%7D%7B10.81%20%7D%3D2.312673451%20%5C%20mol%20%5C%20B)
<u>2. Convert Moles to Atoms</u>
We use Avogadro's Number, 6.02*10²³: the number of particles (atoms, molecules, etc.) in 1 mole of a substance. In this case, the particles are atoms of boron.
![\frac {6.02*10^{23} \ atoms \ B} {1 \ mol \ B}](https://tex.z-dn.net/?f=%5Cfrac%20%7B6.02%2A10%5E%7B23%7D%20%5C%20atoms%20%5C%20B%7D%20%7B1%20%5C%20mol%20%5C%20B%7D)
Multiply by the number of moles we calculated.
![2.312673451 \ mol \ B *\frac {6.02*10^{23} \ atoms \ B} {1 \ mol \ B}](https://tex.z-dn.net/?f=2.312673451%20%5C%20mol%20%5C%20B%20%2A%5Cfrac%20%7B6.02%2A10%5E%7B23%7D%20%5C%20atoms%20%5C%20B%7D%20%7B1%20%5C%20mol%20%5C%20B%7D)
The moles of boron cancel.
![2.312673451 *\frac {6.02*10^{23} \ atoms \ B} {1 }](https://tex.z-dn.net/?f=2.312673451%20%20%2A%5Cfrac%20%7B6.02%2A10%5E%7B23%7D%20%5C%20atoms%20%5C%20B%7D%20%7B1%20%7D)
![2.312673451 *6.02*10^{23} \ atoms \ B} =1.39269195*10^{24} \ atoms \ B](https://tex.z-dn.net/?f=2.312673451%20%20%2A6.02%2A10%5E%7B23%7D%20%5C%20atoms%20%5C%20B%7D%20%3D1.39269195%2A10%5E%7B24%7D%20%5C%20atoms%20%5C%20B)
The original value of grams has 4 significant figures, so our answer should have the same. For the number we calculated, that is the thousandth place.
![1.392\underline69195*10^{24} \ atoms \ B](https://tex.z-dn.net/?f=1.392%5Cunderline69195%2A10%5E%7B24%7D%20%5C%20atoms%20%5C%20B)
The 6 tells us to round the 2 to a 3.
![1.393 *10^{24} \ atoms \ B](https://tex.z-dn.net/?f=1.393%20%2A10%5E%7B24%7D%20%5C%20atoms%20%5C%20B)
25.00 grams of boron is equal to 1.393*10²⁴ atoms.
B. Biomass
(I guess so cause other ones are already being used)
I believe its
a)224000
b)0.000000015
c)0.655
d)9000
<span>[Ni(en)3]SO4
en does not have charge, so
Ni²⁺SO4²⁻,
</span>Ni²⁺
![{\orange { \mathbb{ \huge{QUESTION}}}}](https://tex.z-dn.net/?f=%20%7B%5Corange%20%7B%20%5Cmathbb%7B%20%5Chuge%7BQUESTION%7D%7D%7D%7D)
WHAT IS AN IONIC BOND
![\huge\boxed{\fcolorbox{red}{blue}{ ANSWER }}](https://tex.z-dn.net/?f=%5Chuge%5Cboxed%7B%5Cfcolorbox%7Bred%7D%7Bblue%7D%7B%20ANSWER%20%7D%7D)
![\orange{\underline{\huge{\bold{\textit{\green{\bf{Ionic \:Bond}}}}}}}](https://tex.z-dn.net/?f=%20%5Corange%7B%5Cunderline%7B%5Chuge%7B%5Cbold%7B%5Ctextit%7B%5Cgreen%7B%5Cbf%7BIonic%20%5C%3ABond%7D%7D%7D%7D%7D%7D%7D)
kossel explained that inert gases r inert due to the electronic configuration which contains 8 electrons in their outermost shell
And other elements loss and gain electrons to form ions and to have electronic configuration same as Noble gas and to get stable
#SARDAR JI.