The ML of 0.85 m NaOH required to titrate 25 ml of 0.72m hbr to the equivalence point is calculated as follows
calculate the moles of HBr used
moles = molarity x volume
25 x0.072/1000= 0.0018 moles
write the equation for reaction
NaOH + HBr = NaBr + H2O
from reacting equation the mole ratio between NaOH to HBr is 1:1 therefore the moles of NaOH = 0.0018 moles
volume = moles/molarity
0.0018/0.085 = 0.021 L in Ml = 0.021 x1000=21.18 Ml ofNaOH
The number of moles in 3.20 x 10² formula units of calcium iodide is 0.053 moles.
<h3>How to calculate number of moles?</h3>
The number of moles in the formula units of a substance is calculated by dividing the formula unit by Avogadro's number.
According to this question, 3.20 x 10² formula units are in calcium iodide. The number of moles is as follows:
no of moles = 3.20 x 10²² ÷ 6.02 × 10²³
no of moles = 0.53 × 10-¹
no of moles = 0.053 moles
Therefore, the number of moles in 3.20 x 10² formula units of calcium iodide is 0.053 moles.
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Answer:
the are coefficients for the atom. the tell how many there are.
Explanation:
they tell you how many atoms there are of its type.
ex. 4 C²H³. there are 4 of the c² and h³ (couldn't find a way to use subscript so used the power signs to show.)