Answer:
An ionic bond is an attraction between ions of opposite charge in an ionic compound.
you would change one element to a diffrent element
1) we calculate the molar mass of He (helium) and Kr (Krypton).
atomic mass (He)=4 u
atomic mas (Kr)=83.8 u
Therefore the molar mass will be:
molar mass(He)=4 g/mol
molar mass(Kr)=83.8 g/mol.
1) We can find the next equation:
mass=molar mass x number of moles.
x=number of moles of helium
y=number of moles of helium.
(4 g/mol) x +(83.8 g/mol)y=103.75 g
Therefore, we have the next equation:
(1)
4x+83.8y=103.75
2) We can find other equation:
We have 30% helium atoms and 70% Kryptum atoms, therefore we have 30% Helium moles and 70% of Krypton moles.
1 mol is always 6.022 * 10²³ atoms or molecules, (in this case atoms).
Then:
x=number of moles of helium
y=number of moles of helium.
(x+y)=number of moles of our sample.
x=30% of (x+y)
Therefore, we have this other equation:
(2)
x=0.3(x+y)
With the equations(1) and (2), we have the next system of equations:
4x+83.8y=103.75
x=0.3(x+y) ⇒ x=0.3x+0.3y ⇒ x-0.3x=0.3y ⇒ 0.7 x=0.3y ⇒ x=0.3y/0.7
⇒x=3y/7
We solve this system of equations by substitution method.
x=3y/7
4(3y/7)+83.8y=103.75
lower common multiple)7
12y+586.6y=726.25
598.6y=726.25
y=1.21
x=3y/7=3(1.21)/7=0.52
We have 0.52 moles of helium and 1.21 moles of Krypton.
1 mol=6.022 * 10²³ atoms
Total number of particles=(6.022 *10²³ atoms /1 mol) (number of moles of He+ number of moles of Kr).
Total number of particles=6.022 * 10²³ (0.52+1.21)=6.022 * 10²³ (1.73)=
=1.044 * 10²⁴ atoms.
Answer: The sample have 1.044 * 10²⁴ atoms.
<span>I am sure these answers are correct cause I've checked all of them. Here they are :
1) The thing which might h</span>appen to the rest of the water is that 61% of that water leaves the ground through evapotranspiration and <span>38% will flow into the Atlantic Ocean.
</span>
2) The four states which receive drinking water from Florida are : <span> South Carolina, Georgia, Alabama, Mississippi
3) The</span> reason why people in Florida wanted to get rid of the water in certain areas is abundance of wetlands. I think there is one more, if it is acceptable I suggest you using this - frequent flooding.<span>
4) </span><span> The negative result of the changes which people made to get rid of the water is the first sign of </span>drought.
5) The thing that has been done to try and improve those mistakes was creating a tool which looked like a dam to prevent dfficulties with <span>navigating the state.
Hope that helps.</span>
Answer:
Water has a chemical formula of H2O . In here, there are two hydrogen atoms and one oxygen atom, and so its mass will be 2+16=18 amu . There are two water molecules formed, and that means the total mass of the products is 18⋅2=36 amu .