Answer:C2H6N
Explanation:
Putrescine formula is C4H12N2
Assuming 100g sample is present
The percent changes to grams and it is converted to moles by dividing it with the atomic masses.
C= 54.50g/12 = 4.541moles
H = 13.73g/1 = 13.73moles
N= 31.77g/14 = 2.269moles
Divide through with the smallest moles value.
C= 4.541/2.269 = 2
H= 13.73/2.269=6
N= 2.269/2.269=1
Therefore the empirical formula is
C2H6N
Answer is: the compound is B₂O₃.
ω(O) = 68.94% ÷ 100%.
ω(O) = 0.6894; percentage of oxygen in the compound.
ω(X) = 31.06% ÷ 100%.
ω(X) = 0.3106; percentage of unknown element in the compound.
If we take 69.7 grams of the compound:
M(compound) = 69.7 g/mol.
n(compound) = 69.7 g ÷ 69.7 g/mol.
n(compound) = 1 mol.
n(O) = (69.7 g · 0.6894) ÷ 16 g/mol.
n(O) = 3 mol.
M(compound) = n(O) · M(O) + n(X) · M(X).
n(X) = 1 mol ⇒ M(X) = 21.7 g/mol; there is no element with this molecular weight.
n(X) = 2 mol ⇒ M(X) = 10.85 g/mol; this element is boron (B).
Answer:
[A] = 1.438M = 1.4M (Two s.f)
Explanation:
Rate constant, k = 0.00317
Initial Concentration, [A]o = 1.44M
Final Concentration, [A] = ?
Time, t = 0.240 s
Since this is a second order reaction, the formula for this is given as;
1 / [A] = 1 / [A]o + kt
1 / [A] = 1 / 1.44 + (0.00317 * 0.240)
1 / [A] = 0.6944 + 0.0007608
1 / [A] = 0.6952
[A] = 1.438M = 1.4M (Two s.f)
This has four neutrons and three protons. Additionally, it has three electrons in the electron cloud. A elements number of neutrons will also be an elements atomic number on the periodic table. So, this means that the Bohr model is representing the element Lithium.
Hope this helps :)
Answer:
<u>20.25 mL.</u>
Explanation:
The volume of base required for the titration can be derived by removing the base titrant volume from the volume at endpoint.
i.e Final volume - initial volume
= (22.08 - 1.83)mL
<u>= 20.25 mL.</u>
<em>(Repeat and average volume results for accuracy.)</em>