A model showing that gases are made from the matter of particles that are too small to see and are moving freely around in space can explain many observations.
Magnesium (Mg) has atomic number 12 with electronic configuration :
The valence shell of Mg is 3s which has 2 electrons as shown in above electronic configuration.
Therefore, A = 3 and B =2
Answer:
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Explanation:
Approximately 2 mL of Solution A (on the left) is added to a sample of Solution B (on the right) with a dropping pipet. If a precipitate forms, the resulting precipitate is suspended in the mixture. The mixture is then stirred with a glass stirring rod and the precipitate is allowed to settle for about a minute.
Solution A: 0.5 M sodium hydroxide, colorless
Solution B: 0.2 M nickel(II) nitrate, green
Precipitate: light green
Ni(NO3)2(aq) + 2 NaOH(aq) —> Ni(OH)2(s) + 2 NaNO3(aq)
Credits:
Design
Kenneth R. Magnell Central Michigan University, Mt. Pleasant, MI 48859
John W. Moore University of Wisconsin - Madison, Madison, WI 53706
Video
Jerrold J. Jacobsen University of Wisconsin - Madison, Madison, WI 53706
Text
Kenneth R. Magnell Central Michigan University, Mt. Pleasant, MI 48859
