11 protons and 10 electrons
Calcium has atomic number 20. A neutron calcium atom therefore has 20 protons and 20 electrons. Ca2+ has a charge of positive 2, so it must have 2 more protons than electrons. Ca2+ has 18 electrons.
The main reason that electrons and protons are dominant in matter is that these are stable particles and do not decay spontaneously. The neutron, which is unstable outside of a nucleus, is stable within the nucleus of an atom. The reason that the protons and neutrons are bound together is the strong nuclear force. The coulombic attraction between protons and electrons then binds the electrons to the nucleus to form an atom.
Protons are equivalent to a couple of things, one of which you may not be aware of. First of all, they are equivalent to the nucleus of a hydrogen atom. Additionally, they are equivalent to two up quarks plus one down quark. Why? Because quarks are the fundamental particles that comprise both protons and neutrons, and the combination of quarks written above is what makes up protons.
The number of protons in an atomic nucleus can change by several different mechanisms. Let's look at each one and see what happens.In an atom with "too many" protons in its nucleus, that unstable atom can undergo what is called beta decay. There are two types of beta decay, and the one that could happen here goes by the name beta plus decay. In beta plus decay, a proton in the nucleus of that unstable atom transforms into a neutron. A positron and an antineutrino will be ejected from the nucleus, and the number of protons will have gone down by one. If you guessed that nuclear transmutation has just occurred where one element has transformed into another one, you'd be correct.In some other unstable atoms with "too many" protons in the nucleus, that nucleus could under an electron capture event. In electron capture, the nucleus "pulls in" a nearby electron from one of the inner shells of the atom, and that electron "combines" with a proton to become a neutron. Again, the number of protons in the nucleus goes down by one, and nuclear transmutation has occurred.Lastly, it is possible to bombard atomic nuclei with particles and "knock" protons out of a nucleus that is "hit" by the bombarding particles. There are a few different activities that are carried out in nuclear physics labs to do this, but we'll leave it here for now. Just keep in mind that beta plus decay and electron capture are the two primary methods that unstable nuclei undergo when they change the number of protons they have. Links to related questions can be found below for more information.
YEP! remember In science in order for the Alkali metals and Alkaline earth metals to become stable they must give AWAY electrons. The Earth metals have a Plus 2 charge because they give away 2 electrons on there outer shell!
19 Protons and 20 electrons
Three protons and two electrons.
29 protons and 27 electrons
Mn has 25 protons.
The ion carbon C4+ has 6 protons and 2 electrons.
29 protons and 27 electrons.
Protons: 20 Electrons: 18 Neutrons: 21
Be2+ ion has 4 protons and 2 electrons
Lead will always have 82 protons. If it has a 2+ charge, that means there are 2 more protons than electrons, so there are 80 electrons.
Fe 2+ (Iron) has... 26 protons 24 electrons 30 neutrons
23 electrons, 26 protons, 30 neutrons.
Magnesium has 12 protons and electrons and 12, 13 or 14 neutrons, depending on the isotope.