In general chemistry, isotopes are a group of substances that belong to the same element. An element is characterized in the periodic table by their atomic number, which is the number of protons in an atom. Therefore, these substances have the same atomic numbers, but differ in mass numbers. Mass number is the sum of the number of protons and neutrons in the nucleus of an atom.
To determine the atomic weight of an element, you take the average weight of all the existent isotopes of that said element. The calculation would require to multiply the exact mass of the isotope to its abundance. Then, sum them all up.
Atomic weight = 98(0.18) + 112(0.82)
Atomic weight = 109.48 amu
Answer:
helium hydrogen
Explanation:
lithium beryllium bottom carbon
At STP one mole of any gas occupies 22.4 L
moles NO2 = 99.0/22.4 = 4.42
mass NO2 = 4.42 mol x 46.0 g/mol=203 g
Anything with a pH level of 3, 2, or 1.
I would have to say the answer is a. True.