Solve and round to the correct number of significant figures: 129 ÷ 29.20

Chemistry

1 answer:

Scilla [17]3 years ago

5 0

4.42

Because when you divide 129/29.20, you get a long string of numbers. 4.417808219178082...

So you round to the significant figure which in this case is 2 decimal places because 29.20 has 2 decimal places.

PS did you draw that car? Cuz im into drawing cars too.

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Answer:Your answer is A

Explanation:

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3 years ago

The molar solubility of pbi2 is 1.5 103 m.

Vsevolod [243]

Answer: -

Concentration of PbI₂ = 1.5 x 10⁻³ M

PbI₂ dissociates in water as

PbI₂ ⇄ Pb²⁺ + 2 I⁻

So PbI₂ releases two times the amount of I⁻ as it's own concentration when saturated.

Thus the molar concentration of iodide ion in a saturated PbI₂ solution = [ I⁻] =

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2 years ago

When of alanine are dissolved in of a certain mystery liquid , the freezing point of the solution is less than the freezing poin

LenaWriter [7]

The question is incomplete, the complete question is:

When 177. g of alanine $(C_3H_7NO_2)$ are dissolved in 800.0 g of a certain mystery liquid X, the freezing point of the solution is $5.9^oC$ lower than the freezing point of pure X. On the other hand, when 177.0 g of potassium bromide are dissolved in the same mass of X, the freezing point of the solution is $7.2^oC$ lower than the freezing point of pure X. Calculate the van't Hoff factor for potassium bromide in X.

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The expression for the calculation of depression in freezing point is:

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