The chemical compound is barium nitrate.
So ions are atoms that have either gained or lost electrons to complete their energy levels.
In order for a positive ion to be formed, an atom must lose electrons.
In order for a negative ion to be formed, an atom must gain electrons.
When an atom loses and electron, it loses a negative charge and then becomes a positive ion.
Answer:
Petrified wood contains minerals that are only found in fossils.
Explanation:
learned it in school (promise)
Forensic scientists can compare DNA found at a crime scene (from blood or hair, for example) to DNA samples taken from suspects. If there is no match, they may be able to rule out that suspect. If there is a match, police will likely want to take a closer look.
Answer:
Molarity of the solution = 3.000 M
Volume of the solution = 250.0 mL = 0.25 L
moles in 250.0 mL = molarity x volume of the solution
= 3.000 M x 0.25 L
= 0.75 mol
Hence, 0.75 mol of NaCl is needed to prepare 250.0 mL of 3.000 M NaCl solution.
Moles (mol) = mass (g) / molar mass (g/mol)
Moles of NaCl in 250.0 mL = 0.75 mol
Molar mass of NaCl = 58.44 g/mol
Mass of NaCl in 250.0 mL = Moles x Molar mass
= 0.75 mol x 58.44 g/mol
= 43.83 g
Hence, 43.83 g of NaCl is needed to prepare 250.0 mL of 3.000 M solution.
Explanation:
