1 point

explain why the sun appers to be the brightest star in the sky. relate your explanation with an example such as street lights. t

Zarrin [17]

Answer:

The sun is a star but It is the brightest in the sky because it is the closest star to earth.

I don't know how to compare it to street lights though...

Explanation:

7 0

3 years ago

(a) Kw = 1.139 × 10⁻¹⁵ at 0°C and 5.474 × 10⁻¹⁴, find [H₃O⁺] and pH of water at 0°C and 50°C.

kondor19780726 [428]

The value of [H₃O⁺] and pH of water at 0°C and 50°C.

0°C value of [H₃O⁺] = 3.375 x 10⁻⁸

50°C value of [H₃O⁺] = 2.340 x 10⁻⁷

pH of water at 0°C = pH = 7.4717

pH of water at 50°C = pH = 6.6308

<h3>pH of water at different level:</h3>

Water with a pH less than 7 is considered acidic, while water with a pH greater than 7 is considered basic. The normal pH range for surface water systems is 6.5 to 8.5, and for groundwater systems is 6 to 8.5. Alkalinity is a measure of a water's ability to withstand a pH change that would cause it to become more acidic.

<h3>According to the given information:</h3>

0°C = Kw = 1.139 × 10⁻¹⁵

50°C = 5.474 × 10⁻¹⁴

Solving at 0°C for [H₃O⁺] and pH. water is neutral therefore its[H₃O⁺] [OH⁻]

are equal [H₃O⁺] = [OH⁻].

Kw = [H₃O⁺] [OH⁻]

Kw = [H₃O⁺]²

[H₃O⁺] = √Kw

= √1.139 × 10⁻¹⁵

= 3.375 x 10⁻⁸

pH = -log[H₃O⁺]

= -log 3.375 x 10⁻⁸

= 7.4717

Solving at 50°C for [H₃O⁺] and pH. water is neutral therefore its[H₃O⁺] [OH⁻]

are equal [H₃O⁺] = [OH⁻].

Kw = [H₃O⁺] [OH⁻]

Kw = [H₃O⁺]²

[H₃O⁺] = √Kw

= √ 5.474 × 10⁻¹⁴

= 2.340 x 10⁻⁷ M

pH = -log[H₃O⁺]

= -log2.340 x 10⁻⁷

pH = 6.6308

The value of [H₃O⁺] and pH of water at 0°C and 50°C.

0°C value of [H₃O⁺] = 3.375 x 10⁻⁸

50°C value of [H₃O⁺] = 2.340 x 10⁻⁷

pH of water at 0°C = pH = 7.4717

pH of water at 50°C = pH = 6.6308

To know more about pH of water visit:

brainly.com/question/13822050

#SPJ4

I understand that the question you are looking for is:

Kw = 1.139 × 10⁻¹⁵ at 0°C and 5.474 × 10⁻¹⁴, find [H₃O⁺] and pH of water at 0°C and 50°C. find the [H₃O⁺] and pH of water at 0°C and 50°C.

3 0

1 year ago

What is another name for the sugars organisms use for energy?1. Proteins2. Nucleic acids3. Carbohydrates4. Lipids

victus00 [196]

Answer:

Carbohydrates or Carbs have sugar molecules! :3 hope this helped you

Explanation:

4 0

3 years ago

using the soubility curve what is the solubilityof nh4cl in 10 mL of water at a temperature of 60 degrees Celsius

lukranit [14]

Answer:

Please, see attached two figures:

The first figure shows the solutility curves for several soluts in water, which is needed to answer the question.

The second figure shows the reading of the solutiblity of NH₄Cl at a temperature of 60°C.

Answer: <u>5.5g</u>

Explanation:

The red arrow on the second attachement shows how you must go vertically from the temperature of 60ºC on the horizontal axis, up to intersecting curve for the <em>solubility</em> of <em>NH₄Cl.</em>

From there, you must move horizontally to the left (green arrow) to reach the vertical axis and read the solubility: the reading is about in the middle of the marks for 50 and 60 grams of solute per 100 grams of water: that is 55 grams of grams of solute per 100 grams of water.

Assuming density 1.0 g/mol for water, 10 mL of water is:

$10mL\times 1.0g/mL=10g$