Answer:

Explanation:
In this question, we wish to find the missing nuclei for the equation:

In order to find the missing species, we need to use the charge and mass balance law. That is, the mass should be conserved: the total mass on the left-hand side with respect to the arrow should be equal to the total mass on the right-hand side with respect to the arrow:

Notice from here that:

So far we know that the mass of X is 4. Similarly, we apply the law of charge conservation. The total charge should be conserved:

From here:

We have a particle:

Looking at the periodic table, an atom with Z = 2 corresponds to helium. This can also be written as an alpha particle:

All are true except the statement that ions are formed by changing the number protons in an atom’s nucleus.
A neutral atom contains the same number of protons (positive charge) and electrons (negative charge).
If there are <em>more electrons than protons</em>, the atom becomes a <em>negative ion</em>.
If there are <em>fewer electrons than protons</em>, the atom becomes a <em>positive ion</em>.
The protons are in the nucleus, where we can’t easily get at them. The <em>electrons are outside the nucleus</em>, so other chemicals can easily get at them and either remove them or add to their number.
<em>Metals</em> have only a few valence electrons, so it is fairly easy to remove them and <em>form positive ions</em>.
The answer is Potassium Sulfide
Answer:
If each element can be identified by its spectrum then the composition of an unknown star can be determined
Explanation:
The chemical nature of the elements is that they absorb specific wavelength of light depending on their atom. By spectral analysis of the spectrum of emitted light by a body, the body's composition can therefore be determined. As such in order to determine the composition of distant bodies such as planets, stars and other celestial bodies scientists usually make use of spectroscopy.
Answer : There are many ways to use electric current, but as you have asked for only three, here are some of them along with the change in their energy transformations;
1) Using a light bulb which consumes electrical energy and the energy is transformed into light energy, making everything visible for us.
2) Using a power tool makes use of electrical energy and the energy is transformed into mechanical energy for multipurpose use of cutting woods.
3)
Using electrical iron converts electrical energy into thermal energy to heat the iron and enables the user to iron crease-free clothes.