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:
Mn (s) + NiCl2 (aq) → MnCl2 (aq) + Ni
Explanation:
The order of displacement of metals from aqueous solution by another metal is defined by the activity series of metals.
The activity series arranges metals in order of reactivity and increasing electrode potentials. The less negative the electrode potential of a metal is, the less reactive it is and the lower it is found in the activity series.
Nickel has a less negative electrode potential than manganese hence it is displaced from an aqueous solution of its salt by manganese spontaneously.
The pressure of a sample of a gas if the temperature is changed to 127 c while the volume remains constant is calculated using gay lussac law formula
that is P1/T1 = P2/V2
P1 = 100 torr
T1 = 27+273 = 300 k
T2 =127 +273 =400 k
P2=?
by making P2 the subject of the formula
P2=T2P1/T1
=100 x 400/300 = 133.3 torr