<span>A. the number of perching birds present</span>
Answer: Aluminum is in group IIIA of the periodic table therefore it has three valence electrons. The symbol for aluminum is Al which will be surrounded by three dots. 2.
Explanation:
Answer:
Slide a magnet through the mixture. When you take the magnet off, the iron filings are going to be attracted to the magnet and the sand will stay in the bowl
Explanation:
Temporary hardness can be dealt with using boiling water(Calcium hydrogen carbonate) but Permanent won't so you need to use washing soda instead(sodium carbonate) or Ion exchange resin