How many atoms are contained in 3.46 moles of magnesium

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

2 years ago

Gallium is produced by the electrolysis of a solution made by dissolving gallium oxide in concentrated NaOH ( aq ) . Calculate t

Sedbober [7]

Answer:

Approximately $6.30\times 10^{-3}\;\rm mol$ .

Explanation:

The gallium here is likely to be produced from a $\rm NaGaO_2\, (aq)$ solution using electrolysis. However, the problem did not provide a chemical equation for that process. How many electrons will it take to produce one mole of gallium?

Note the Roman Numeral " $\mathtt{(III)}$ " next to $\rm Ga$ . This numeral indicates that the oxidation state of the gallium in this solution is equal to $+3$ . In other words, each gallium atom is three electrons short from being neutral. It would take three electrons to reduce one of these atoms to its neutral, metallic state in the form of $\rm Ga\, (s)$ .

As a result, it would take three moles of electrons to deposit one mole of gallium atoms from this gallium $\mathtt{(III)}$ solution.

How many electrons are supplied? Start by finding the charge on all the electrons in the unit coulomb. Make sure all values are in their standard units.

$t = \rm 80.0\; min = 80.0\; min \times 60\;s \cdot min^{-1} = 4800\; s$ .

$Q = I \cdot t = \rm 0.380 \; A \times 4800 \; s = 1.824\times 10^3\; C$ .

Calculate the number of electrons in moles using the Faraday's constant. This constant gives the size of the charge (in coulombs) on each mole of electrons.

$\begin{aligned} n(\text{electrons}) &= \frac{Q}{F} \cr &= \rm \dfrac{1.824\times 10^3\; C}{96485.332\; C \cdot mol^{-1}}\cr &\approx \rm 1.89\times 10^{-2}\; mol \end{aligned}$ .

It takes three moles of electrons to deposit one mole of gallium atoms $\rm Ga\, (s)$ . As a result, $\rm 1.89\times 10^{-2}\; mol$ of electrons would deposit $\displaystyle \rm \frac{1}{3}\times 1.89\times 10^{-2}\; mol \approx 6.30\times 10^{-3}\; mol$ of gallium atoms $\rm Ga\, (s)$ .

8 0

2 years ago

A main group metal was studied and found to exhibit the following properties:

Alecsey [184]

Answer: we learned this not to long ago i think its a,c

Explanation:

6 0

3 years ago

Explain why BH3 is trigonal planar and NH3 is trigonal pyramidal.

Troyanec [42]

Answer:o It is important to realise that mixing will be small unless there are electrons in the 4a1 LUMO, this is why NH3 is pyramidal while BH3 is planar! ... This mixing is very strong and stabilises the 3a1 MO substantially and hence NH3 is trigonal pyramidal and not planar.

Explanation:

3 0

2 years ago

El agua con trozos de hielo es heterogenea o homogenea

dimaraw [331]

El agua con hielo es sistema heterogénea .

4 0

2 years ago