Answer: <u>IONIC BONDING- </u>When a metallic atom reacts with a non metallic atom, then it forms an ionic bond. For example, Sodium (Na) is a metal that reacts with a non-metal Chlorine (Cl) forming Sodium-chloride (NaCl).
<u>COVALENT BONDING-</u> It is a chemical bonding that occurs when any two non-metallic atoms reacts with one another, by sharing one pair of electrons. For example, Carbon Dioxide (CO₂).
Yes. Brain cells need oxygen to survive.
Red and blue, only the red and blue ends of the visible part of the electromagnetic spectrum are used by plants in photosynthesis.