A chemical element that has an atomic number less than 58 and an atomic mass greater than 135.6m is barium (atomic no. 56 and atomic mass137.13 ) and lanthanum (atomic no. 57 and atomic mass 135.6).
<h3>Give a brief introduction about Barium and Lanthanum.</h3>
Barium is an element with the symbol Ba and atomic number 56. It is an alkaline earth metal that is soft and silvery, and it is the fifth element in group 2. Barium is never found in nature as a free element due to its extreme chemical reactivity. Oil well drilling fluid uses barium sulfate as an insoluble ingredient. It is employed as an X-ray radiocontrast agent in a purer form to image the human gastrointestinal tract. Barium compounds that dissolve in water have been employed as rodenticides despite being hazardous.
Chemical element lanthanum has the atomic number 57 and the symbol La. It is a silvery-white, ductile, soft metal that slowly tarnishes when exposed to air. It serves as the eponym for the group of 15 related elements in the periodic table between lanthanum and lutetium, of which lanthanum is the first and prototype. The rare earth elements traditionally include lanthanum.
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Answer: option a and d
Explanation:
Option A- Benzene undergoes substitution reaction
Example : benzene reacts with chlorine to form chlorobenzene, in the presence of Iron
(iii) chloride as a catalyst
C6H6 + Cl2 ---> C6H5Cl + HCl
Option D- Benzene also undergoes addition reaction
Example: benzene reacts with hydrogen , in the presence of nickel as a catalyst to form
cyclohexane
C6H6 + 3H2 ---> C6H12
Reasons why Option B isn't the answer
Although benzeme has degree of unsaturation but it's not five degree of unsaturation.
Benzene has 6 carbon atoms and 4 degrees of unsaturation (1 ring and 3 double
bonds).
If you work backwards and double the degrees of unsaturation you have 8 degrees of
unsaturation instead of 5.
Option C - Benzene isn't a saturated hydrocarbon
Central "carbon" atom
2 oxygen atoms
held together by "covalent" bonds
has a "1s2 2s2 2px1 2py1 2pz0" electron
geometry
carbon atom is "sp" hybridized
Answer:
A. It formed by barium(Ba+2) ion and sulfate ( SO42- )
B. It is formed by calcium ion (Ca+2) and two fluoride ions (2F-)
C. It is formed by magnesium ion (Mg+2) and nitride ion (N3-)
D. It is formed by two potassium ions (2 K+) and oxide ion(O2-)
Answer:
10. mol NaOH
Explanation:
2.5 M = 2.5 mol/L
2.5 mol/L * 4 L = 10. mol
