There are about 7 or 8 primary tectonic plates. The lithosphere is made of about a dozen plates. The plates fit together like the pieces of a jigsaw puzzle. However, the plates can move. This causes earthquakes, volcanoes, and mountains to form.
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The answer would be .5 mols because you take the total amount of grams, which is 20, and you had up the molar mass of sodium hydroxide, which would be 40. After you have this you would set this up as a stochiometry equation. With 1 mol on top you dived 20/40 to cancel out your grams. This leaves you with .5 mols
8/5lit.. of 12M NaOH
2/5lit.. of 2M NaOH
The grams of water produced is c
a) Group 2 elements have 2 electrons on their outer shell, so they form a 2+ charge.
b) they lose 2 electrons as they are transferred to the non metal.
c)They obtain this charge as when they are made into an ionic compound the 2 electrons on the outer shell are transferred to the non metal, meaning there are 2 more protons that electrons, giving it a positive charge.
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