Answer:
It’s true ( pure).
Explanation:
An element is defined as a pure substance that is not chemically combined with any other elements. An element comprises of mainly the sane type of atoms.
While a compound is a substance that consists of two or more elements which are chemically combined together. This is the main difference between an element and a compound.
Its going to be 2.81 x 1023 atoms
Answer:
Copper Atoms
Explanation:
All copper atoms have atomic number 29: all their nuclei contain 29 protons. But they also contain uncharged particles called neutrons. In natural copper, the atoms are of two kinds. One has 29 protons and 34 neutrons in the nucleus; the other has 29 protons and 36 neutrons
Dots are used to represent electrons.
To determine the relative atomic mass of thallium, we multiply the molar mass of the isotopes to their corresponding relative abundance. The molecular percentages should sum up to 1. In this case, we multiply 203 by 0.295 and 205 by 0.705 and add the answers of the two. The final atomic mass is 204.41 g/mol.