102 grams.
Equation:
Quantify of heat = mass x specific heat x difference in temperature
We have: quantity of heat : 2300J
specific heat: .449 J/g
difference in t: 80 - 30 = 50
Solve for mass: 2300 = mass x 0.449 x 50
mass = 102.449
2 sig-figs --> 102 grams
Answer:
The molecular weight is 
Explanation:
From the question we are told that
The mass of the sample is 
The temperature is 
The volume which the gas occupied is 
The pressure is 
Generally from the ideal gas equation we have that

Here n is the number of moles of the gas while the R is the gas constant with value 

=> 
=> 
Generally the molecular weight is mathematically represented as

=> 
=> 