Answer:
It is called liquid gold because of its high price and value and its economic need by all the countries worldwide.
Explanation:
Petroleum is present in abundant quantity in the some regions . So it is considered as Liquid gold, which they value a lot.
This is false. The amount of electrons in lithium (Li) is not 7, it is 3. There are 3 electrons in lithium.
Answer:
The plum-pudding model did not identify a central nucleus as the source of a positive charge.
Explanation:
Sir Joseph John Thomson, most popularly known as J J Thomson. He was a famous scientist who was awarded the Noble prize for Physics for his discovery of the subatomic particle, electron.
He placed his famous model of an atom which is known as plum pudding model. He proposed that the atoms are described as the negative particles that is floating within a soup of the diffuse positive charge.
But the main defect of his proposal was that it did not recognized the presence of a central nucleus as a positive charged source.
Answer: Group 1 would have the lowest electronegativity values.
Explanation:
Electronegativity is the power of an atom in a molecule to attract electrons. It is also synonymous with the oxidizing ability or non-metallic character of elements.
Generally, across a given period from left to right, electronegativity increases due to increasing nuclear charge and decreasing atomic radius ( or atomic size ). This is because there is a greater tendency for a smaller atom with higher nuclear attraction to attract electrons than a larger atom with a lower nuclear attraction due to the shielding effect of the nuclear attraction by the inner shell electrons on the outermost electrons in the larger atom.
Also, down a particular group, electronegativity generally decreases due to increasing atomic radius/size.
This is why metals are generally electropositive ( lose electrons ) and non-metals are electronegative ( gain electrons ) as they are both found more on the left and right sides of the periodic table respectively.
