Answer:
Helium is the second element on the periodic table. It is located in period 1 and group 18 or 8A on the righthand side of the table. This group contains the noble gases, which are the most chemically inert elements on the periodic table. Each He atom has two protons and usually two neutrons and two electrons.
Explanation:
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Answer:
The following reaction will occur at cathode:

Explanation:
The two half reaction during electrolysis of aqueous nickel sulfate will be
a) anode reaction :
Water will undergo oxidation and will evolve oxygen gas at anode as shown in the given reaction:

b) Cathode reaction: The reduction of Nickel ion will occur by gain of two electrons as shown in the given equation:

Thus the overall reaction will be:

Petrified fossils, they are made of wood that becomes petrified from pressure and lack of oxygen.
Answer:
1.5g
Explanation:
According to this question, the amount of copper required to obtain copper sulfide in a 4:1 is 6g. This means that the ratio of copper to sulfur in the compound (copper sulfide) is 4:1.
Hence, to calculate the amount of sulfur required for the reaction to obtain copper sulfide using the above ratio, we say:
1/4 of the amount of copper required (6g)
= 1/4 × 6
= 6/4
= 1.5g of sulfur is required for the reaction to obtain carbon sulfide.