Answer:
Two electrons fit in the first shell out from the nucleus and eight fit in the second. Every element with more protons than the two of Helium needs to work on shells outside the first one. one you get to ten, you have filled the first two shells.
In a water molecule, oxygen forms one covalent bond with EACH of TWO hydrogen atoms. As a result, the oxygen atom has a stable arrangement of 8 valence electrons. Each hydrogen atom forms only one bond because it needs only two electrons to be stable.
86 elections so 43 orbitals
Answer:
There is 2.52 kJ of energy released (option 4)
Explanation:
Step 1: Data given
The enthalpy of fusion of methanol (CH3OH) is 3.16 kJ/mol
Mass of methanol = 25.6 grams
Molar mass of methanol = 32.04 g/mol
Step 2: Calculate moles of methanol
Moles methanol = mass methanol / molar mass methanol
Moles methanol = 25.6 grams / 32.04 g/mol
Moles methanol = 0.799 moles
Step 3: Calculate energy transfer
Energy transfer = moles * enthalpy of fusion
Energy = 0.799 moles * 3.16 kJ/mol
Energy = 2.52 kJ released
There is 2.52 kJ of energy released
Adult Bone Marrow has stem cells that are not as "good" as embryonic ones but they still can become red blood and skin cells
Answer:
92.49 %
Explanation:
We first calculate the number of moles n of AgBr in 0.7127 g
n = m/M where M = molar mass of AgBr = 187.77 g/mol and m = mass of AgBr formed = 0.7127 g
n = m/M = 0.7127g/187.77 g/mol = 0.0038 mol
Since 1 mol of Bromide ion Br⁻ forms 1 mol AgBr, number of moles of Br⁻ formed = 0.0038 mol and
From n = m/M
m = nM . Where m = mass of Bromide ion precipitate and M = Molar mass of Bromine = 79.904 g/mol
m = 0.0038 mol × 79.904 g/mol = 0.3036 g
% Br in compound = m₁/m₂ × 100%
m₁ = mass of Br in compound = m = 0.3036 g (Since the same amount of Br in the compound is the same amount in the precipitate.)
m₂ = mass of compound = 0.3283 g
% Br in compound = m₁/m₂ × 100% = 0.3036/0.3283 × 100% = 0.9249 × 100% = 92.49 %
