Why did you post this again? Because you're lazy and wanted people to not see my post? Once again, ONE QUESTION AT A TIME. We're here to help you with a tough question or work you through it, not do all your homework.
<span>Here are some
pH < 7
Sour taste (though you should never use this characteristic to identify an acid in the lab)
Reacts with a metal to form hydrogen gas Increases the H+ concentration in water
Donates H+ ions<span>
Turns blue litmus indicator red</span></span>
Answer:
the sum of the numbers of protons and neutrons present in the nucleus of an atom.
