Hi!
Magnets attract with opposite poles. The reason is the North pole of a magnet's magnetic lines (if that makes any sense) generally flow inwards, making it pulling in, and the South pole's magnetic lines flow outwards, pushing out. If you align two magnets with the same poles together, they will always repel, because they will be flowing in different directions.
However, if you align a north and a south pole together, they will work together, and attract.
Therefore, if you place two magnets randomly, and they're close enough, they'll align so that the north pole of one magnet faces the south pole of the other magnet, or choice A.
5.515km.
With BIDMAS, you would do the addition first and then do the subtraction.
Answer:
524.82 g Cl2
Explanation:
Balanced Equation:
2Al(s) + 3Cl(g) ⇒ 2AlCl (s)
Al: 26.982 g/mol Cl: 35.453 g/mol
266.28g Al x 1mol Al/ 26.982g Al x 3mol Cl2/ 2mol Al x
35.453g Cl2/ 1mol Cl2 = 524.82 g Cl2
Mass of each silver coin = 5.67 g
Molar mass of silver = 107.87 g/mol
Calculating the moles of silver from given mass and molar mass of silver:
Calculating the atoms of silver in 0.05260 mol using the conversion factor, 
:
Therefore, 
atoms of silver are present in each coin.
