Answer:
Option (D)
Explanation:
Oil (crude and petroleum) is one of the major resources on earth in which the economy of a country is largely dependent on. These are non-renewable resources, which take thousands to million years of years in order to form.
It is highly essential. Every day, a large quantity of oil is being consumed. According to the researches done in the year 2015, it has been observed that the average global consumption of oil was 95 million barrels each day.
It has a high demand, and so it is being regularly used, and it has also been predicted that the present global oil reserves would be highly exhausted within the next 50 years.
Thus, the correct answer is option (D).
Answer:
Atoms have protons and neutrons in the center, making the nucleus, while the electrons orbit the nucleus. The modern atomic theory states that atoms of one element are the same, while atoms of different elements are different.Atoms consist of three basic particles: protons, electrons, and neutrons. The nucleus (center) of the atom contains the protons (positively charged) and the neutrons (no charge). The outermost regions of the atom are called electron shells and contain the electrons (negatively charged).
A chemical equation does not give information about the following:
- It usually does not give the "state of the substances". There are three states: Solid(s), liquid(q) and gas(vap).
- The chemical equation does not show whether it is complete or incomplete.
- The "speed of the reaction" is not mentioned.
- The "concentration of the substance" whether it is diluted or concentrated is not mentioned.
- The "rate of the reaction", temperature, catalyst, pressure etc is not mentioned. These can be mentioned "above or below the arrow".
What element has the same number of orbits as Hydrogen? Why? Do they have similar properties, why?
Answer:
Helium
Explanation:
Helium has the same number of orbitals as hydrogen because they belong to the same period on the periodic table.
Periods are the horizontal arrangement of elements. Elements in the same period are known to have the same number of electronic shell or orbitals.
In period 1 where we have just Hydrogen and Helium, the number of orbitals is 1.
For properties of a specie, elements in the same group which are the vertical arrangement of elements have the same properties. Since both Hydrogen and helium are in different groups, their properties differ.
