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olasank [31]
3 years ago
7

Use the helium-4 isotope to define atomic number and mass number. why does knowledge of atomic number enable us to deduce the nu

mber of electrons present in an atom
Chemistry
1 answer:
Nuetrik [128]3 years ago
8 0
Helium - 4 isotope has 2 protons and 2 neutrons.

Its atomic number is 2 (the number of protons). Atomic number is the number of protons in the atom of an element and it identifies the element. All the isotopes of an element have the same atomic number (same number of protons). So, all the isotopes of hellium have 2 protons.

The number 4 that identifies the helium - 4 isotope is the mass number, i.e. the number of protons plus the number of neutron. So, helium-4 isotope has 2 protons and 2 neutrons. While, other isotopes of helium have 2 protons but different number of neutrons.

The atomic number enable us to deduce the number of electrons in an atom because the atoms are neutral, which implies that the positive and negative charge are equal. Given that the magnitude of the charge of electons and protons are equal but the sign is opposed (protons are positve and electrons are negative) the number of electrons in the atom equals the number of protonts. That is why the atomic number is also the number of electrons of the atom.
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How does the automatic hammer convert gravitational potential energy into kinetic energy?
Nutka1998 [239]

Answer:

Exolaiend in explanation section

Explanation:

First of all, the automatic hammer is used to drive nails into tight spaces where where we can't get a sufficient striking force if we are to use a normal regular hammer in driving the nail.

So the nail to be driven is lifted out of rest(it's position). The energy here is gravitational potential energy.

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8 0
3 years ago
How could natural selection lead to speciation?
Harlamova29_29 [7]

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Speciation can be driven by evolution, which is a process that results in the accumulation of many small genetic changes called mutations in a population over a long period of time. ... Natural selection can result in organisms that are more likely to survive and reproduce and may eventually lead to speciation.

I hope it's helpful!

6 0
2 years ago
The sturdy wall outside of a skyscraper could be most easily compared to
Flauer [41]
I think the answer is A because the job of a cell membrane is to provide protection to the plant. A cell membrane has a sturdy wall.
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2 years ago
how do I do this I’m confused
Naily [24]

by using pro.gram..

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4 0
3 years ago
Can someone help me out with this?
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