The unknown metal with a mass of 39.27 g is potassium with the symbol K.
The mass of an atom is due to protons and neutrons present in it.
The protons and neutrons are together present in the nucleus of an atom.
The mass of any element is given by its mass number whose formula is
Mass Number = Number of protons + Number of neutrons
In the given case 39 = Number of protons + Number of neutrons
The only element of the periodic table which satisfies the above equation is potassium because it has 19 protons and 20 neutrons.
Thus, the unknown metal with a mass of 39.27 g is potassium with the symbol K.
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Your answer is c. homologous structures
Answer:
It has only 1 electron in its valence shell and if that electron is removed it will acquire noble gas configuration
Explanation:
Sodium forms an ion of charge +1 as in its ionic state it has inert gas configuration
It forms an ion of charge +1 when the valence shell electron is removed to gain the noble gas configuration and the electrons can be removed mostly from its valence shell because inner shell electrons will be tightly bounded to the nucleus of the atom and it requires high energy to remove the electron present in the inner shell when compared to the valence shell (outermost shell)
Answer:
The valence electrons determine an atom's reactivity.
Explanation:
The valence electrons is the electrons on the most outer layer of an atom. The higher the number of valence electrons, the bigger the reactivity of the atom. This means that when that atom is put with another substance and it reacts, it would react in a much more violent way than another atom with lower valence electrons.
Answer:
Explanation:
Assume that the bullet is shot at a velocity of (v m/s) and it will take t time to pass the second plate.
by the definition of then angular velocity (ω)
ω=\frac{angular displacement}{time }[/tex]
Lets find the time to turn the next plate by 12 degrees , using θ=ωt
]t=\frac{12}{8995.5} =1.334*10^{-3}[/tex]
the bullet has to travel 80cm in this much of time to make a hole in the second plate. We can find the speed using this equation
(we have to convert cm into meters first)