An arctic weather balloon is filled with 20.9l of helium gas inside a prep shed. the temperature inside the shed is 13 degree c. the balloon is then taken outside, where the temperature is -9 degree c. calculate the new volume of the balloon. you may assume the pressure on the balloon stays constant at exactly 1 atm. round your answer to significant digits.

hey there!

The combined gas equation is  :

P1V1/T1 = P2V2/T2  

Since Pressure is constant for this question it will cancel out leaving  

V1/T1 = V2/T2  

where  :

V1 = initial volume = 20.9 L  

T2 = initial temp (must be in Kelvin) = 286 K  

V2 = final volume = ? L  

T2 = final temp = 264 K  

Solve for V2  

V2 = V1T2 / T1  

= 20.9 L * 264 K / 286 K  

= 19.29 L  

= 19.3 L (3 sig digits)

Hope this helps!

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.

the answer is the first option

explanation:

just googled it m8. not that hard

lol