Answer:
4
Explanation:
Carbon has four valence electrons, so it can achieve a full outer energy level by forming four covalent bonds. When it bonds only with hydrogen, it forms compounds called hydrocarbons. Carbon can form single, double, or triple covalent bonds with other carbon atoms.
The periodic table only accounts for elements. It does not account for compounds, such as water.
The neurotransmitter is Dopamine.
The following combinations of neurotransmitters seem to be at play in
those who suffer from ADHD is Serotonin, dopamine, and norepinephrine. Neurotransmitters,
also known as chemical messengers, are endogenous chemicals that enable
neurotransmission. They transmit signals across a chemical synapse, such as a
neuromuscular junction.