Half life is 100 years.
after 1st life the number of isotopes remaining =100/2=50
after 2nd half life the number of isotopes remaining=50/2=25
Answer:
As you turn the tube you can see patterns of colors at the other end of the tube. A kaleidoscope works by reflecting light. Light travels in a straight line. When light bumps into something it changes direction.
Kaleidoscopes are made with two or more mirrors. Light reflecting between these mirrors produces multiple virtual images of stunning beauty. ... Light rays are assumed to bounce off the mirrors like a ball bounces off a hard surface. Formally stated, the angle of incidence equals the angle of reflection.
Explanation:
Answer:
V₁ = 10 mL
Explanation:
Given data:
Initial volume of HCl = ?
Initial molarity = 3.0 M
Final molarity = 0.10 M
Final volume = 300.0 mL
Solution:
Formula:
M₁V₁ = M₂V₂
M₁ = Initial molarity
V₁ = Initial volume of HCl
M₂ =Final molarity
V₂ = Final volume
Now we will put the values.
3.0 M ×V₁ = 0.10 M×300.0 mL
3.0 M ×V₁ = 30 M.mL
V₁ = 30 M.mL /3.0 M
V₁ = 10 mL
Answer:
-484kJ
Explanation:
Carry out bond energy calculation
[6(C-H) + (C=O) +2(C-C)] - [(O-H) +7(C-H)+ (C-O) +2(C-C)]
Substitute the bond energy values = -484kJ