Explanation:
1) from the periodic table for example if u looking for K it is from the group 1A so the valancey = +1 that is mean it loses one electron to reach a stable state. and this applied for the 1A , 2A, 3A groups.
if u looking for N it is from group 5A so its valency is -3
so it gain 3 electrons to reach a stable state to complete its orbital to 8 electrons. this applied to 5A, 6A,7A
for the transition metals and simimetals other rules.
2) neutral if the element does not hold any charge like
H2, O2, N2, Fe, Au, Cu ...
isotope : if the 2 elements have same symbol and atomic number but they differ in the mass number because the have different numbers of neutrons.
if the element is charged then it is considered as an ion ex: Fe2+ then it is iron cation ( +ion)
F- then it is fluoride anion (-ion)
if u have any doubt just writ a comment ( ;
Answer:
Wavelength, 
Explanation:
We have,
Velocity of the object, 
Mass of the object, 
It is required to find the wavelength of the object. The relation between wavelength and velocity of the object is given by :

h is Planck's constant

So, the wavelength of the object is
.
It is really difficult to dissolve the sulfur substance because not only is it polar, but it is composed of long S-chains and not only atoms. So, water cannot dissolve the sulfur because nonpolar compounds do not dissolve in polar solvents. Sulfur doesn't always dissolve with nonpolar solvents, as well. However, since carbon disulfide also contains S-chains, it is the best solvent that would dissolve sulfur.
Answer:
these micronutrients are not produced in our bodies and must be derived from the food we eat.
Explanation:
Vitamins and minerals are micronutrients required by the body to carry out a range of normal functions. However, these micronutrients are not produced in our bodies and must be derived from the food we eat. Vitamins are organic substances that are generally classified as either fat soluble or water soluble.
The answer is <span>Plastics, Medicine, Clothing, Paper. </span>Coal is used in the making of Plastics, Medicine, Clothing, Paper. Some important users of coal include alumina refineries, paper manufacturers, and the chemical and pharmaceutical industries. Thousands of different products have coal or coal by-products as components: soap, aspirins, solvents, dyes, plastics and fibres, such as rayon and nylon.