A 1.0-mol sample of an isotope is decaying with a half-life of 28 ...

[genevieve1028]

A 1.0-mol sample of an isotope is decaying with a half-life of 28 y. After 61 y, how many moles of this isotope are left and what is its activity in Bq?
 
  What will be an ideal response?

Question 2

What is the steady state rate of heat flow through a pane of glass that is 40.0 cm by 30.0 cm with a thickness of 4.00 mm when the outside temperature of the glass is -10.0C and its inside temperature is 25.0C?
 
  The thermal conductivity of glass is 0.105 W/(mK), the specific heat of glass is 0.180 cal/(gC), and 1 cal = 4.190 J.
  A) 3.81 W B) 110 W C) 24.2 W D) 47.3 W E) 18.6 W

[Silverbeard98]

Answer to Question 1

0.22 mol, 1.0  1014 Bq

Answer to Question 2

B