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2 years ago

The molarity of a solution prepared by dissolving 4.11 g of NaI in enough water to prepare 312 mL of solution is

Chemistry

1 answer:

Dimas [21]2 years ago

6 0

Answer:

The correct answer is 8.79 × 10⁻² M.

Explanation:

Based on the given information, the mass of NaI given is 4.11 grams. The molecular mass of NaI is 149.89 gram per mole. The moles of NaI can be determined by using the formula,

No. of moles of NaI = Weight of NaI/ Molecular mass

= 4.11 / 149.89

= 0.027420

The vol. of the solution given is 312 ml or 0.312 L

The molarity can be determined by using the formula,

Molarity = No. of moles/ Volume of the solution in L

= 0.027420/0.312

= 0.0879 M or 8.79 × 10⁻² M

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On a coordinate plane, which single transformation could map point A (3,-4) onto point A' (1.5,-2)? *

Ksenya-84 [330]

Answer: A dilation with rule: $(x,y)\to(\dfrac12x,\dfrac12y)$

Explanation:

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(kx,ky) = corresponding coordinate in the image.

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Using scale factor k= $\dfrac12$ , we have

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2 years ago

A Student Formulated A Hypothesis That Cotton Will Grow Larger Bolls ( Pods ) If Magnesium Is Added To The Soil. The Student Has

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3 years ago

A 1.00 liter solution contains 0.43 M hydrofluoric acid and 0.56 M potassium fluoride. If 0.280 moles of potassium hydroxide are

kolbaska11 [484]

Answer:

Answers are in the explanation

Explanation:

Equlibrium of HF in H₂O is:

HF + H₂O ⇄ F⁻ + H₃O⁺

Now, the KOH reacts with HF, thus:

KOH + HF → F⁻ + H₂O

That means after reaction, concentration of HF decrease increasing F⁻ concentration.

Now, seeing the equilibrium, as moles of HF decrease and F⁻ moles increase, the equilibrium will shift to the left decreasing H₃O⁺ concentration.

For the statements:

A. The number of moles of HF will increase. FALSE. HF react with KOH, thus, moles of HF decrease

B. The number of moles of F- will decrease. FALSE. The reaction produce F⁻ increasing its moles.

C. The equilibrium concentration of H₃O⁺ will increase. FALSE. The equilibrium shift to the left decreasing concentration of H₃O⁺

D. The pH will decrease. FALSE. As the H₃O⁺ concentration decrease, pH will increase

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3 years ago

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The density at 1,291 km from the surface of the planet is

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3 years ago

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grigory [225]

Answer:

See explanation.

Explanation:

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2 years ago