1 mole=6.02 x 10^23 atoms so how many moles are there in 3.0 x 10^23 we will cross multiply, 1 x 3.0 x 10^23 / 6.02 x 10 ^23. Which will give us 0.498 moles.
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Answer:
Which is the ph of a solution in which the concentration of hydroxide ion is greater than the concentration of hydrogen ion?
An acidic solution is one in which the hydrogen ion concentration is greater than the hydroxide ion concentration; in other words, the hydrogen ion concentration is greater than 1 X 10-7 M, and the hydroxide ion concentration is less than 1 X 10-7 M. In terms of pH, an acidic solution has a pH less than 7
Explanation:
Bromide gives away 1 electron (valency of 1) and Ca wants to gain 2 electrons (valency of 2) therefore 2 Br ions are needed