Concept explainers
Interpretation:
The terms
Concept introduction:
The total number of protons in an atom is said to be its atomic number. By using the total number of protons and neutrons all the atoms can be identified. Atomic number is denoted by “Z”.
The total number of neutrons and protons of an atom is said to be its mass number. By using the total number of protons and neutrons all the atoms can be identified. Mass number is denoted by “A”.
An atom is always said to be neutral. Therefore for the charge to remain neutral the total number of electrons must be equal to total number of protons and hence, the atomic number is same as the total number of electrons.
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Chemistry: Atoms First
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- Here are three fictitious elements and a molecular view of the atoms that compose them. The molar mass of the middle element, (b), is 25 grams per dozen (g/doz). (The atoms of these fictitious elements are much larger than ordinary atoms.) Based on the size of the atoms, do you expect the atomic masses of elements (a) and (c) to be greater than or less than (b)? How many atoms are present in 175 g of element (b)?arrow_forwardArgon has three naturally occurring isotopes: 0.3336% 36Ar, 0.063% 38Ar, and 99.60% 40Ar. Estimate the average atomic mass of argon. If the masses of the isotopes are 35.968 u, 37.963 u, and 39.962 u, respectively, calculate the average atomic mass of natural argon.arrow_forwardA single molecule has a mass of 7.31 1023 g. Provide an example of a real molecule that can have this mass. Assume the elements that make up the molecule are made of light isotopes where the number of protons equals the number of neutrons in the nucleus of each element.arrow_forward
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