Answer:
a.Archaeopteryx
b.Archaeopteryx had more in common with other small Mesozoic dinosaurs than with modern birds.Archaeopteryx was generally accepted by palaeontologists and popular reference books as the oldest known bird.Archaeopteryx could grow to about 0.5 m (1 ft 8 in) in length.
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Answer:
78.4%
Explanation:
yield = actual/theoretical = 7.84/10 = 78.4%
Answer:- Oxidation number of Cl does not change as it is -1 on both sides.
Explanations:- oxidation number of Mg on reactant side is 0 as it is in its elemental form(not combined with another element).
Oxidation number of hydrogen in its compounds is +1, so if H is +1 in HCl the oxidation number of Cl is -1 as the sum has to be zero.
On product side, Mg oxidation number is +2 as the oxidation number of alkaline earth metals in their compounds is +2.
Two Cl are present in magnesium chloride, so if Mg is +2 then Cl is -1.
Oxidation number of H on product side is 0 as it is present in its elemental for,
,
So, it is only chlorine(Cl) whose oxidation number does not change for the given equation.
In the equation given above, there is conservation of MASS, CHARGE AND ENERGY.
These three parameters are usually conserved during the course of chemical reactions. When any of these parameter experience a reduction during the course of chemical reaction, such loss is always gained by other elements involved in the same reaction, so that at the end of the day, they are not considered as lost.