Answer:
B) System.
Explanation:
It is a group of parts working together. They work together to make a whole, therefore they are all a system when working together.
An ionic bond is formed by the transfer of electrons from one atom to the other. It is usually formed between a metal + non-metal.
A covalent bond is formed by sharing of electrons between two atoms. It is formed between two nonmetals. A polar covalent bond is formed between 2 non-metals which differ in their electronegativities. In contrast, in a non-polar covalent interaction the two atoms could either be the same or have very close electronegativities.
1) P and I : Both non-metals with different electronegativities= Polar Covalent
2) Fe and O: Metal + non-metal = Ionic
3) S and Cl: Both non-metals with different electronegativities= Polar Covalent
4) S and S: Both non-metals and the same atoms = Non-polar Covalent
5) Br and Br: Both non-metals and the same atoms = Non-polar Covalent
6) O and Cl: Both non-metals with different electronegativities= Polar Covalent
7) Be and Cl: Metal + non-metal = Ionic
8) Al and N: Metal + non-metal = Ionic
Answer: Nail moving towards a magnet
Explanation: Since the iron nails and pins move towards the magnet, it means that the magnet exerts a force on them. The force exerted by a magnet is called magnetic force.
Answer:
C
Explanation:
an index fossil is a fossil from a very short-lived, geographically widespread species known to exist during a specific interval of geological time.