Atoms are electrically neutral because they contain equal quantities of positively charged protons and negatively charged electrons. Electrons and protons have equal but opposite charges, so the result is no net charge. Ions are atoms that have gained or lost electrons.
Answer:
30 μmol/L
Explanation:
<em>A chemist prepares a solution of barium chloride by measuring out 8.9 μmol of barium chloride into a 300mL volumetric flask and filling the flask to the mark with water.
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Calculate the concentration in μmol L of the chemist's barium chloride solution. Round your answer to 2 significant digits.</em>
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The chemist has 8.9 μmol of solute (barium chloride) and he adds water until the mark of 300 mL in the container, which is the volume of the solution. We will need the conversion factor 1 L = 1000 mL. The concentration of barium chloride in μmol/L is:

Answer:
Explanation: you need to remove the subscript of 5
Th first one is Iron and the second one is Xenon