Answer:
21 years
% of parent isotope remaining before safe
6.25%
Explanation:
Answer & Explanation:
D orbitals begin filling with electrons after the orbital found in the 4s sublevel is filled. This occurs because the d sublevel is first found in the.
1) Chemical equation
<span>2NH4Cl(s)+Ba(OH)2⋅8H2O(s)→2NH3(aq)+BaCl2(aq)+10H2O(l)
2) Stoichiometric ratios
2 mol NH4Cl(s) : 54.8 KJ
3) Convert 24.7 g of NH4Cl into number of moles, using the molar mass
molar mass of NH4Cl = 14 g/mol + 4*1 g/mol + 35.5 g/mol = 53.5 g/mol
number of moles = mass in grams / molar mass
number of moles = 24.7 g / 53.5 g/mol = 0.462 moles
4) Use proportions:
2 moles NH4Cl / 54.8 kJ = 0.462 moles / x
=> x = 0.462 moles * 54.8 kJ / 2 moles = 12.7 kJ
Answer: 12.7 kJ
</span>
First we need to calculate the number of moles of FeS
:
number of moles = mass (grams) / molecular mass (g/mol)
number of moles of FeS
= 198.2/120 = 1.65 moles
From the chemical reaction we deduce that:
if 4 moles of FeS
produces 8 moles of SO
then 1.65 moles of FeS
produces X moles of SO
X = (1.65×8)/4 = 3.3 moles of SO
Now we can calculate the mass of SO
:
mass (grams) = number of moles × molecular mass (grams/mole)
mass of SO
= 3.3×64 = 211.2 g
<span>Most bonds are made when a positive atom or molecule (one that is missing an electron in its outer shell) accepts an electron from a negative atom or molecule. Hydrogen is a positive ion because it only has one electron in its outer shell instead of a pair. Oxygen has paired electrons, but because it is highly electronegative one of the outer electrons is held closer to the nucleus, creating a partial negative charge. This partial negative charge attracts the electron in the outer shell of hydrogen and creates a bond. This type of bond accounts for the high surface tension in water.</span>