If we laid each atom end-to-end, they would reach about 20 times the distance from Earth to the Moon.
<em>Assum</em>e that sand has a density of 2 g/cm³ and consists of units of SiO₂.
<em>V</em> = 1 mm³ × (1cm/10 mm)³ = 1 × 10⁻³ cm³
Mass = 1 × 10⁻³ cm³ × (2 g/1 cm³) = 2 × 10⁻³ g
Moles of SiO₂ = 2 × 10⁻³ g × (1 mol SiO₂/60.08 g SiO₂) = 3 × 10⁻⁵ mol SiO₂
Units of SiO₂ = 3 × 10⁻⁵ mol SiO₂ × (6.022 × 10²³ units SiO₂/1 mol SiO₂)
= 2 × 10¹⁹ units SiO₂
Atoms = 2 × 10⁻¹⁹ units SiO₂ × (3 atoms/1 unit SiO₂) = 6 × 10¹⁹ atoms
<em>Assume</em> that each atom has a diameter of 140 pm. If we laid them end to end, they would stretch for
6 × 10¹⁹ atoms × (140 × 10⁻¹² m/1 atom) = 8 × 10⁹ m = 8 × 10⁶ km
That’s 20 times the distance from Earth to he Moon.
Answer:
Kelvin is considered to be the best scale for measuring temperature for two reasons: 1, Because the Kelvin scale defines what we mean by temperature. Other scales are now defined in terms of the Kelvin scale
Explanation:
The mass that the aerogel insulation added to the aircraft, with respect to glass, is 8.8 × 10³ g.
The density of the aerogel is 0.00011 lb/in³. We will convert it to g/cm³ using the following conversion factors:
![\frac{0.00011lb}{in^{3} } \times \frac{454g}{1lb} \times \frac{1in^{3} }{16.4cm^{3} } = 0.0030 g/cm^{3}](https://tex.z-dn.net/?f=%5Cfrac%7B0.00011lb%7D%7Bin%5E%7B3%7D%20%7D%20%5Ctimes%20%5Cfrac%7B454g%7D%7B1lb%7D%20%5Ctimes%20%5Cfrac%7B1in%5E%7B3%7D%20%7D%7B16.4cm%5E%7B3%7D%20%7D%20%3D%200.0030%20g%2Fcm%5E%7B3%7D)
If the maximum space for insulation in the spacecraft's hull was 2921 cm³, the mass that would occupy the aerogel with a density of 0.0030 g/cm³ is:
![2921 cm^{3} \times \frac{0.0030g}{cm^{3} } = 8.8 g](https://tex.z-dn.net/?f=2921%20cm%5E%7B3%7D%20%5Ctimes%20%5Cfrac%7B0.0030g%7D%7Bcm%5E%7B3%7D%20%7D%20%3D%208.8%20g)
Glass is about 1000 times denser than aerogel. That is,
![0.0030 g/cm^{3} \times 1000 = 3.0 g/cm^{3}](https://tex.z-dn.net/?f=0.0030%20g%2Fcm%5E%7B3%7D%20%5Ctimes%201000%20%3D%203.0%20g%2Fcm%5E%7B3%7D)
If the maximum space for insulation in the spacecraft's hull was 2921 cm³, the mass that would occupy the glass with a density of 3.0 g/cm³ is:
![2921 cm^{3} \times \frac{3.0g}{cm^{3} } = 8.8 \times 10^{3} g](https://tex.z-dn.net/?f=2921%20cm%5E%7B3%7D%20%5Ctimes%20%5Cfrac%7B3.0g%7D%7Bcm%5E%7B3%7D%20%7D%20%3D%208.8%20%5Ctimes%2010%5E%7B3%7D%20%20g)
The mass that would add the aerogel with respect to the glass is:
![8.8 \times 10^{3} g - 8.8 g \approx 8.8 \times 10^{3} g](https://tex.z-dn.net/?f=8.8%20%5Ctimes%2010%5E%7B3%7D%20%20g%20-%208.8%20g%20%5Capprox%208.8%20%5Ctimes%2010%5E%7B3%7D%20%20g)
The mass that the aerogel insulation added to the aircraft, with respect to glass, is 8.8 × 10³ g.
You can learn more about density here: brainly.com/question/18320053
Is this for science class I need more info to answer the following question
Answer: The correct answer is: " endothermic . "
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<u>Note</u>: Heat flows <u> into </u> [heat <u> may be </u> absorbed within] an "<u>endothermic</u>" reaction or system
To the contrary, heat flows <u> </u><u>out </u> [heat <u> may </u><em> </em>exit from or <u> may be </u> released from] an "<u>exothermic</u>" reaction or process.
<u>Hint</u>: Think of the "prefixes" of: "<u>endo</u>thermic" and "<u>exo</u>thermic" :
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1) endo- = "within" (as in "endothermic" —heat tends to be absorbed/"within"/"released within"/released within"/into" ;
2) exo- = " outwards"/"exit" (as in "exothermic") —heat tends to '"exit"/leave/escape from/"be released out of/form".
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Hope this is helpful to you!
Best wishes to you in your academic pursuits
—and within the "Brainly" community"!
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