The two main types of bonds formed between atoms are ionic bonds and covalent bonds. An ionic bond is formed when one atom accepts or donates one or more of its valence electrons to another atom. A covalent bond is formed when atoms share valence electrons.
<span>Thin, flattened, and typically curved bones, such as the ribs or sternum, form falt bones.
The two main functions of flat bones are protection or provide a large surface for musular attachment.
These are the flat bones of the human body: in the skull, parietal, frontal, occipial, lacrimal, nasal and vomer; scapula; sternum; rib and hip.
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B. The surface of a silver cup turns black when it is exposed to air.
