Question 4 of 10
2 points
what is the internal energy of 7.00 mol of n2 gas at 40°c? to solve this
problem, use the equation: udiatomie gas =
remember that r=8.31 j/(mol-k) and k = °c + 273.
o a 45.500
o b. 5820
o c. 11,600
o d. 18.2003

A. 45500 J

Explanation:

Internal energy of diatomic gas is:

U = 5/2 nRT

where n is the number of moles,

R is the universal gas constant,

and T is the absolute temperature.

Given n = 7.00 mol, R = 8.31 J/mol/K, and T = 40+273 = 313 K:

U = 5/2 (7.00 mol) (8.31 J/mol/K) (313 K)

U = 45500 J

  1.the balanced   chemical equation is as below

cu +   2 ag(no)₃ → cu(no₃)₂   +2 ag

2.the   much silver   produced   is   50.9 g

step 1: find the   moles of cu

moles =   mass÷   molar mass

  from periodic table the molar mass of cu = 63.5 g/mol

moles is therefore = 15.00 g÷ 63.5 g/mol = 0.236   moles

step 2: use the mole ratio to determine the   moles of ag

from equation above   cu: ag   is 1: 2

therefore the moles of ag   =0.236   moles   x 2/1 =0.472   moles

step 3: find the mass   of ag

mass = moles x molar mass

from periodic table   the molar mass of ag =107.87 g/mol

mass   = 0.472   moles x 107.87 g/mol = 50.9 g

3.   the   much   silver   collected worth is   1.797 oz

  convert   50.9 g   to oz

that is   1 gram = 0.0353 oz

          50.9 grams =?   oz

by cross multiplication

={(50.9 grams x 0.0353 oz) / 1   gram}   =1.797 oz