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3 years ago

The concentrations of hydrogen ion in two solutions are (a).1×10-4moldm and (b).5×10-9moldm. What is the pH of each solutions?

Chemistry

1 answer:

Svet_ta [14]3 years ago

4 0

Answer:

(a) pH=4.0

(b) pH=8.3

Explanation:

Hello there!

In this case, since the pH is understood as the potential of the hydrogen in an aqueous solution, and we can calculate it is as follows:

$pH=-log([H^+])$

We simply need to plug in the concentrations on each question as shown below:

(a)

$pH=-log(1x10^{-4})\\\\pH=4$

(b)

$pH=-log(5x10^{-9})\\\\pH=8.3$

Regards!

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Write 0.00000009345 in Engineering Notation with 3 significant figures

melisa1 [442]

Answer:

$93.43\times 10^{-9}$

Explanation:

Scientific notation is the way of writing numbers which are either large or small. The number is written in the scientific notation when the number is between 1 and 10 and then multiplied by the power of 10. Engineering notation is the same version of the scientific notation but the number can be between 1 and 1000 and in this exponent of the ten is divisible by three.

For example, $1000^2$ is to be written as $10^6$ in engineering notation.

The given number:

0.00000009345 can be written as $93.425\times 10^{-9}$

Answer upto 4 significant digits = $93.43\times 10^{-9}$

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2 years ago

Name NaCl; is it a) molecular b) ionic c) elemental d) strong electrolyte, e) weak electrolyte f) non-electrolyte g) acid h) bas

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Answer:

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Explanation:

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It is also called common salt or table salt as it is used as edible in daily our life.

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2 years ago

What is the percentage strength (w/w) of a solution made by dissolving 62.5 g of potassium chloride in 187.5 ml of water?

kiruha [24]

Percent strength (% w/w) of a solution is defined as the amount of solute present in 100 g of the solution.

Given data:

Mass of the solute, potassium chloride = 62.5 g

Volume of water (solution) = 187.5 ml

We know that the density of water = 1 g/ml

Therefore, the mass corresponding to the given volume of water

= 187.5 ml * 1 g/1 ml = 187.5 g

We have a solution of 62.5 g of potassium chloride in 187.5 g water

Therefore, amount of solute in 100 g of water= 62.5 * 100/187.5 = 33.33

The percentage strength = 33.33 %

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3 years ago

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Explanation:

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2 years ago

Fatty acids spread spontaneously on water to form a monomolecular film. A solution containing 0.10 mm^3 of a fatty acid is dropp

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Divide the volume by the area. Using scientific makes things a bit cleaner.

$0.10\,\mathrm{mm}^3 = 10^{-1}\,\mathrm{mm}^3$

$400.\,\mathrm{cm}^2 = 4\times10^2\,\mathrm{cm}^2$

Then

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Now, 1 m = 10⁹ nm, so

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1 year ago