Answer:
Number of moles of sodium reacted = 0.707 moles
Explanation:
P(H₂) = P(T) – P(H₂O)
P(H₂) = 754 – 17.5 = 736.5 mm Hg
Use the ideal gas equation which
PV= nRT, where P is the pressure V is the volume, n is the number of moles R is the Gas Constant and T is temperature
<u>Re- arrange to calculate the number of moles and using the data provided</u>
n = P x V/R x T
n =736.5 x 8.77/62.36367 x (mmHg/mol K) x (20 + 273)
n = 0.35348668
n = 0.353 moles H₂
<u>from the equation we know that</u>
0.353 mole H₂ x 2mole Na/1mole H₂, So
0.353 x 2 = 0.707 mole Na
The number of moles of Sodium metal reacted were 0.707 moles.
Answer:
Scandium
Explanation:
Mendeleev played an important role in the development of the modern periodic table. His periodic table was filled with gaps. He said that these gaps were elements that were yet to be discovered. He rightly predicted many elements which have now been discovered and fitted in their proper places in the periodic table.
He used the prefix ''eka'' to refer to elements whose properties were alike but were yet to be discovered at that time.
The compound named ekaboron which he predicted to have an atomic weight between 65 (zinc) and 75 (arsenic) with a valence similar to aluminum was later discovered in 1879 and properly named scandium.
Elemental copper would be a pure substance.
Answer:
trans-1,3-pentadiene is more stable than 1,4-pentadiene due to presence of a conjugated double bond.
Explanation:
Here, 
H(hydrogenated pdt.) is same for both 1,4-pentadiene and 1,3-pentadiene as they both produce pentane after hydrogenation
H(diene) depends on stability of diene.
More stable a diene, lesser will be it's H(diene) value (more neagtive).
trans-1,3-pentadiene is more stable than 1,4-pentadiene due to presence of a conjugated double bond.
Hence, 
is higher (less negative) for trans-1,3-pentadiene
