Read the information about the three atoms given in the table. Which of them are isotopes of each other

When the temperature of the air is 25°C, the velocity of a sound wave traveling through the air is approximately

Vitek1552 [10]

Answer ; The correct answer is : 346 m/s .

Sound is a type of longitudinal wave , which is produced when a matter compress or refracts .

Speed of sounds depends on factors like medium , density , temperature etc .

Effect of Temperature on speed of sounds :

When the temperature increases , molecules gains energy and they starts vibrating and with higher temperature vibration becomes fast . So the waves of sounds can travel faster due to faster vibrations . Hence , speed of sounds is directly proportional to the temperature or speed of sounds increases with increase in temperature .

The speed of sounds at 0⁰C is 331 $\frac{m}{s}$

The relation between speed of sound and temperature is given as :

$V = 331 \frac{m}{s} + ( 0.6 \frac{m}{s- ^0C} * T )$

Given : Temperature = 25 ⁰ C

Plugging values in formula =>

$V = 331 \frac{m}{s} + (0.6 \frac{m}{s-^0C} * 25^0C)$

$V = 331 \frac{m}{s} + 15 \frac{m}{s}$

$V = 346 \frac{m}{s}$

7 0

3 years ago

"How much NH4Cl, when present in 2.00 liters of 0.200 M ammonia, will give a solution with pH = 8.20? For NH3, Kb = 1.8 x 10-5"

Andru [333]

Answer:

245.66g of NH₄Cl is the mass we need to add to obtain the desire pH

Explanation:

The mixture of NH3/NH4Cl produce a buffer. We can find the pH of a buffer using H-H equation:

pH = pKa + log [A⁻] / [HA]

Where [A⁻] is the molar concentration of the base, NH₃, and [HA] molar concentration of the acid, NH₄⁺. This molar concentration can be taken as the moles of each chemical

First, we need to find pKa of NH₃ using Kb. Then, the moles of NH₃ and finally replace these values in H-H equation to solve moles of NH₄Cl we need to obtain the desire pH.

pKa NH₃/NH₄⁺

pKb = - log Kb

pKb = -log 1.8x10⁻⁵ = 4.74

pKa = 14 - pKb

pKa = 14 - 4.74

pKa = 9.26

Moles NH₃

2.00L ₓ (0.200mol NH₃ / L) = 0.400 moles NH₃

H-H equation:

pH = pKa + log [NH₃] / [NH₄Cl]

8.20 = 9.26 + log [0.400 moles] / [NH₄Cl]

-1.06 = log [0.400 moles] / [NH₄Cl]

0.0087 = [0.400 moles] / [NH₄Cl]

[NH₄Cl] = 0.400 moles / 0.0087

[NH₄Cl] = 4.59 moles of NH₄Cl we need to add to original solution to obtain a pH of 8.20. In grams (Using molar mass NH₄Cl=53.491g/mol):

4.59 moles NH₄Cl ₓ (53.491g / mol) =

<h3>245.66g of NH₄Cl is the mass we need to add to obtain the desire pH</h3>

3 0

4 years ago

Climate is the __________________ average weather conditions that occur in a particular region.

masya89 [10]

Explanation:

Climate is the period of time average weather condition which occurs at a place

6 0

3 years ago

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Which of the following is an example of an abiotic factor? A wind factor B Human C bacterium D duck

solmaris [256]

Abiotic factors, also called abiotic components, are non-living parts of the environment which affects the living organisms and their function in the ecosystem. I think the correct answer is A. Wind factor is the only non-living part from the choices.

7 0

3 years ago

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Which number is the same as 8.7 x 10^-2? A.0.087 B.0.08 C.0.0087 D.0.87

Butoxors [25]

This correct option is C.
10^-2 = 0.001
8.7 * 10^-2 = 8.7 * 0.001 = 0.0087
Thus, 8.7 * 10^-2 is equivalent to 0.0087.

3 0

3 years ago

Read 2 more answers