It would be the skeletal system. This systems primary purpose it to give body its shape, support, protection, and makes new red blood cells from the bone marrow. Located deep inside bones.
The atomic number of a neutral atom is equal to the number of protons and the number of electrons of the atom. The atomic weight meanwhile is equal to the sum of the number of protons and number of neutrons. In this case, the no.of protons is 19 and the number of neutrons is 40-19 equal to 21.
Copper sulphide has the formula CuS and copper sulphate is CuSO4
CuS is a compound of sulphur and copper only while CuSO4 has these 2 elements plus Oxygen
1- because the lid was closed
This site is used for learning, so to give a better understanding, here is a walkthrough.
So let's create a question:
Can a molecule have a dipole moment if it has no polar covalent bonds?
Here's the answer to that question:
Even though a molecule contains only one element, it can have a persistent dipole moment. The most common example is ozone (trioxygen). It is curved and has a partial positive charge on the center oxygen atom (similar to sulfur dichloride).
Permanent dipole moments are caused by an unequal, directed charge distribution within a molecule, not by changes in electronegativity. Such charge distributions are frequently caused by so-called "polar covalent bonds," which occur between atoms with markedly varying electronegativity. However, they are not the sole explanation.
So using this information, try to answer this question on your own.
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