Answer:
Option B is correct.
4
Explanation:
We know that an atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example, if neutral atom has 6 protons than it must have 6 electrons. The sum of neutrons and protons is the mass number of an atom while the number of protons are number of electrons is the atomic number of an atom.
In given problem we are given with 2 neutrons of helium. We know that the atomic number of He is 2. Thus Mass number of He is,
Number of neutrons + number of proton
2 + 2 = 4
Thus, option B is correct.
If you have to write the chemical formula of a simple, binary ionic compound given the name of the compound, you follow a set of three steps. Let's go through them using magnesium chloride as an example. Write the symbols for the cation and the anion: Mg and Cl. Determine the charge on the cation and anion.
<span>Many life forms consist of a single cell. As well as simple bacteria, there are more complex organisms, known as protoctists. Unlike bacteria, they have complex internal structures, such as nuclei containing organized strands of genetic material called chromosomes. Most are single-celled, but some form colonies, with each cell usually remaining self-sufficient.</span>
Answer:
2p
Explanation:
it has 3 dumbell shapes, hence p
you can't determine the principal quantum number by looking at the shape, however bigger or spread orbital means higher value of n
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